Sample records for oversteer

  1. 17 CFR 12.315 - Consequences of overstating damages claims not in excess of $30,000.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Consequences of overstating damages claims not in excess of $30,000. 12.315 Section 12.315 Commodity and Securities Exchanges... Proceedings § 12.315 Consequences of overstating damages claims not in excess of $30,000. If a party, who has...

  2. Overstability and cooling in sunspots

    NASA Technical Reports Server (NTRS)

    Roberts, B.

    1976-01-01

    The role played by overstable Alfven modes in magnetic structures such as sunspots is considered in detail for a column of magnetic field. It is demonstrated explicitly that overstable Alfven waves cool the interior of the magnetic column. It is suggested that these waves account for the cooling in sunspot umbrae, and therefore, in concurrence with Parker, we conclude that a sunspot is a region of enhanced heat transport. The calculations indicate that sunspots have small regions at normal photospheric brightness, and we tentatively suggest that these regions are umbral dots. We also suggest that cooling by overstable Alfven waves may explain the existence of the intense small magnetic flux tubes that constitute the general solar magnetic field.

  3. Maximum Constrained Directivity of Oversteered End-Fire Sensor Arrays

    PubMed Central

    Trucco, Andrea; Traverso, Federico; Crocco, Marco

    2015-01-01

    For linear arrays with fixed steering and an inter-element spacing smaller than one half of the wavelength, end-fire steering of a data-independent beamformer offers better directivity than broadside steering. The introduction of a lower bound on the white noise gain ensures the necessary robustness against random array errors and sensor mismatches. However, the optimum broadside performance can be obtained using a simple processing architecture, whereas the optimum end-fire performance requires a more complicated system (because complex weight coefficients are needed). In this paper, we reconsider the oversteering technique as a possible way to simplify the processing architecture of equally spaced end-fire arrays. We propose a method for computing the amount of oversteering and the related real-valued weight vector that allows the constrained directivity to be maximized for a given inter-element spacing. Moreover, we verify that the maximized oversteering performance is very close to the optimum end-fire performance. We conclude that optimized oversteering is a viable method for designing end-fire arrays that have better constrained directivity than broadside arrays but with a similar implementation complexity. A numerical simulation is used to perform a statistical analysis, which confirms that the maximized oversteering performance is robust against sensor mismatches. PMID:26066987

  4. DAVs: Red Edge and Outbursts

    NASA Astrophysics Data System (ADS)

    Luan, Jing

    2018-04-01

    As established by ground based surveys, white dwarfs with hydrogen atmospheres pulsate as they cool across the temperature range, 12500K< Teff < 10800K . Known as DAVs or ZZ Ceti stars, their oscillations are attributed to overstable g-modes excited by convective driving. The effective temperature at the blue edge of the instability strip is slightly lower than that at which a surface convection zone appears. The temperature at the red edge is a two-decade old puzzle. Recently, Kepler discovered a number of cool DAVs exhibiting sporadic outbursts separated by days, each lasting several hours, and releasing \\sim 10^{33}-10^{34} {erg}. We provide quantitative explanations for both the red edge and the outbursts. The minimal frequency for overstable modes rises abruptly near the red edge. Although high frequency overstable modes exist below the red edge, their photometric amplitudes are generally too small to be detected by ground based observations. Nevertheless, these overstable parent modes can manifest themselves through nonlinear mode couplings to damped daughter modes which generate limit cycles giving rise to photometric outbursts.

  5. Viscous Overstability in Saturn's B-Ring. II. Hydrodynamic Theory and Comparison to Simulations

    NASA Astrophysics Data System (ADS)

    Schmidt, Jürgen; Salo, Heikki; Spahn, Frank; Petzschmann, Olaf

    2001-10-01

    We investigate the viscous oscillatory instability (overstability) of an unperturbed dense planetary ring, an instability that might play a role in the formation of radial structure in Saturn's B-ring. We generalize existing hydrodynamic models by including the heat flow equation in the analysis and compare our results to the development of overstable modes in local particle simulations. With the heat flow, in addition to the balance equations for mass and momentum, we take into account the balance law for the energy of the random motion; i.e., we allow for a thermal mode in a stability analysis of the stationary Keplerian flow. We also incorporate the effects of nonlocal transport of momentum and energy on the stability of the ring. In a companion paper (Salo, H., J. Schmidt, and F. Spahn 2001. Icarus, doi:10.1006/icar.2001.6680) we describe the determination of the local and nonlocal parts of the viscosity, the heat conductivity, the pressure, as well as the collisional cooling, together with their dependences on temperature and density, in local event-driven simulations of a planetary ring. The ring's self-gravity is taken into account in these simulations by an enhancement of the frequency of vertical oscillations Ω z>Ω. We use these values as parameters in our hydrodynamic model for the comparison to overstability in simulated rings of meter-sized inelastic particles of large optical depth with Ω z/Ω=3.6. We find that the inclusion of the energy-balance equation has a stabilizing influence on the overstable modes, shifting the stability boundary to higher optical depths, and moderating the growth rates of the instability, as compared to a purely isothermal treatment. The non-isothermal model predicts correctly the growth rates and oscillation frequencies of overstable modes in the simulations, as well as the phase shifts and relative amplitudes of the perturbations in density and radial and tangential velocity.

  6. The role of collective self-gravity in the nonlinear evolution of viscous overstability in Saturn's rings

    NASA Astrophysics Data System (ADS)

    Lehmann, M.; Schmidt, J.; Salo, H.

    2017-09-01

    Observational evidence for the presence of axisymmetric periodic micro-structure on length scales of 100m - 200m in Saturn's A and B rings was revealed by several instruments onboard the Cassini mission to Saturn. The structure was seen in radio occultations performed by the Radio Science Subsystem (RSS) (Thomson et al. (2007)) and stellar occultations carried out with the Ultraviolet Imaging Spectrograph (UVIS) (Colwell et al. (2007)), and the Visual and Infrared Mapping Spectrometer (VIMS) (Hedman et al. (2014)). Up to date, this micro-structure is best explained by the viscous overstability, which arises as a spontaneous oscillatory instability in a dense ring, if certain conditions are met, leading to the formation of axisymmetric density waves with wavelengths on the order of 100m. We investigate the influence of collective self-gravity forces on the nonlinear, large scale evolution of the viscous overstability in Saturn's rings. To this end we numerically solve the nonlinear hydrodynamic model equations for a dense ring, including radial self-gravity and employing values for the transport coefficients (such as the ring's viscosity and heat conductivity) derived by salo et al. (2001). We concentrate on ring optical depths of order unity, which are appropriate to model Saturn's dense rings. Furthermore, local N-body simulations, incorporating vertical and radial collective self-gravity forces are performed. Direct particle-particle forces are omitted, which prevents small scale gravitational instabilities (self-gravity wakes) from forming, an approximation that allows us to study long radial scales of some 10 kilometers and to compare directly the hydrodynamic model and the N-body simulations. Our hydrodynamic model results, in the limit of vanishing self-gravity, compare very well with the studies of Latter & Ogilvie (2010) and Rein & Latter (2013). In contrast, for rings with non-vanishing radial self-gravity we find that the wavelengths of saturated overstable wave trains tend to settle close to the frequency minimum of the nonlinear dispersion relation, i.e. the saturation wavelengths decrease with increasing surface mass density of the ring. Good agreement between hydrodynamics and N-body simulations is found for disks with strong radial self-gravity, while the largest deviations occur in the limit of weak self-gravity. The resulting saturation wavelengths of the viscous overstability for moderate and strong radial self-gravity (100m-300m) agree reasonably well with the length scale of the axisymmetric periodic micro structure in Saturn's inner A ring and the B ring, as found by Cassini.

  7. Mechanical energy transport. [during stellar turbulences

    NASA Technical Reports Server (NTRS)

    Stein, R. F.; Leibacher, J. W.

    1980-01-01

    The properties, generation, and dissipation mechanisms of acoustic, gravity and Alfven waves are described, whose restoring forces are pressure, buoyancy, and magnetic tension, respectively. For acoustic waves, generation by turbulent convective motions and by the Eddington Valve thermal overstability is discussed, considering the 'five-minute' oscillation; dissipation is possible either by radiation or shocks. Generation of gravity waves by penetrative convective motions and by shear arising from supergranule motions is reviewed, and dissipation due to wave breaking, interaction with the mean horizontal fluid flow, and very severe radiative damping is considered. Attention is given to Alfven wave generation by convective motions and thermal overstability, and to dissipation by mode coupling, wave decay, current dissipation, and particle collisions producing Joule or viscous heating.

  8. How DSH payments might mislead the financial assessment of government-owned hospitals.

    PubMed

    McCue, Michael J; Draper, Debra A

    2004-01-01

    Hospitals are eligible for and receive Medicaid disproportionate share hospital (DSH) payments for caring for the indigent/uninsured; however, county hospitals may also be obligated to transfer these funds to the state. These transfers occur in order for state governments to utilize these funds to receive federal matching funds. Thus, not only do gross DSH payments overstate how much county-owned hospitals have available to cover their financial obligations, they may also overstate the hospital's financial condition. Using detailed California Office of Statewide Health Planning and Development (OSHPD) financial data, this study demonstrates how hospital revenue, profit, and credit measures are overvalued because they do not include the outflow of DSH funds through the intergovernmental transfers (IGTs).

  9. Steering characteristic of an articulated bus under quasi steady maneuvering

    NASA Astrophysics Data System (ADS)

    Ubaidillah, Setiawan, Budi Agus; Aridharma, Airlangga Putra; Lenggana, Bhre Wangsa; Caesar, Bernardus Placenta Previo

    2018-02-01

    Articulated buses have been being preferred as public transportation modes due to their operational capacity. Therefore, passenger safety must be the priority of this public service vehicle. This research focused on the analytical approach of steering characteristics of an articulated bus when it maneuvered steadily. Such turning condition could be referred as a stability parameter of the bus for preliminary handling assessment. The analytical approach employed kinematics relationship between front and rear bodies as well as steering capabilities. The quasi steady model was developed to determine steering parameters such as turning radius, oversteer, and understeer. The mathematical model was useful for determining both coefficients of understeer and oversteer. The dimension of articulated bus followed a commonly used bus as utilized in Trans Jakarta busses. Based on the simulation, for one minimum center of the body, the turning radius was calculated about 8.8 m and 7.6 m at steady turning speed of 10 km/h. In neutral condition, the minimum road radius should be 6.5 m at 10 km/h and 6.9 m at 40 km/h. For two centers of the body and oversteer condition, the front body has the turning radius of 8.8 m, while, the rear body has the turning radius of 9.8 m at both turning speeds of 40 km/h. The other steering parameters were discussed accordingly.

  10. A Weakly Nonlinear Model for the Damping of Resonantly Forced Density Waves in Dense Planetary Rings

    NASA Astrophysics Data System (ADS)

    Lehmann, Marius; Schmidt, Jürgen; Salo, Heikki

    2016-10-01

    In this paper, we address the stability of resonantly forced density waves in dense planetary rings. Goldreich & Tremaine have already argued that density waves might be unstable, depending on the relationship between the ring’s viscosity and the surface mass density. In the recent paper Schmidt et al., we have pointed out that when—within a fluid description of the ring dynamics—the criterion for viscous overstability is satisfied, forced spiral density waves become unstable as well. In this case, linear theory fails to describe the damping, but nonlinearity of the underlying equations guarantees a finite amplitude and eventually a damping of the wave. We apply the multiple scale formalism to derive a weakly nonlinear damping relation from a hydrodynamical model. This relation describes the resonant excitation and nonlinear viscous damping of spiral density waves in a vertically integrated fluid disk with density dependent transport coefficients. The model consistently predicts density waves to be (linearly) unstable in a ring region where the conditions for viscous overstability are met. Sufficiently far away from the Lindblad resonance, the surface mass density perturbation is predicted to saturate to a constant value due to nonlinear viscous damping. The wave’s damping lengths of the model depend on certain input parameters, such as the distance to the threshold for viscous overstability in parameter space and the ground state surface mass density.

  11. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ballouz, Ronald-Louis; Richardson, Derek C.; Morishima, Ryuji

    We study the B ring’s complex optical depth structure. The source of this structure may be the complex dynamics of the Keplerian shear and the self-gravity of the ring particles. The outcome of these dynamic effects depends sensitively on the collisional and physical properties of the particles. Two mechanisms can emerge that dominate the macroscopic physical structure of the ring: self-gravity wakes and viscous overstability. Here we study the interplay between these two mechanisms by using our recently developed particle collision method that allows us to better model the inter-particle contact physics. We find that for a constant ring surfacemore » density and particle internal density, particles with rough surfaces tend to produce axisymmetric ring features associated with the viscous overstability, while particles with smoother surfaces produce self-gravity wakes.« less

  12. The shocking properties of supersonic flows: Dependence of the thermal overstability on M, α, and Tc / T0

    NASA Astrophysics Data System (ADS)

    Pittard, J. M.; Dobson, M. S.; Durisen, R. H.; Dyson, J. E.; Hartquist, T. W.; O'Brien, J. T.

    2005-07-01

    We present hydrodynamical calculations of radiative shocks with low Mach numbers and find that the well-known global overstability can occur if the temperature exponent (α) of the cooling is sufficiently negative. We find that the stability of radiative shocks increases with decreasing Mach number, with the result that M=2 shocks require α ⪉ -1.2 in order to be overstable. Such values occur within a limited temperature range of many cooling curves. We observe that Mach numbers of order 100 are needed before the strong shock limit of α_cr ≈ 0.4 is reached, and we discover that the frequency of oscillation of the fundamental mode also has a strong Mach number dependence. We find that feedback between the cooling region and the cold dense layer (CDL) further downstream is a function of Mach number, with stronger feedback and oscillation of the boundary between the CDL and the cooling region occuring at lower Mach numbers. This feedback can be quantified in terms of the reflection coefficient of sound waves, and in those cases where the cooling layer completely disappears at the end of each oscillation cycle, the initial velocity of the waves driven into the upstream pre-shock flow and into the downstream CDL, and the velocity of the the boundary between the CDL and the cooling layer, can be understood in terms of the solution to the Riemann problem. An interesting finding is that the stability properties of low Mach number shocks can be dramatically altered if the shocked gas is able to cool to temperatures less than the pre-shock value (i.e. when χ < 1, where χ is the ratio of the temperature of the cold dense layer to the pre-shock temperature). In such circumstances, low Mach number shocks have values of α_cr which are comparable to values obtained for higher Mach number shocks when χ = 1. For instance, α_cr=-0.1 when M=2 and χ=0.1, comparable to that when M=10 and χ=1. Thus, it is probable that low Mach number astrophysical shocks will be overstable in a variety of situations. We also explore the effect of different assumptions for the initial hydrodynamic set up and the type of boundary condition imposed downstream, and find that the properties of low Mach number shocks are relatively insensitive to these issues. The results of this work are relevant to astrophysical shocks with low Mach numbers, such as supernova remnants (SNRs) immersed in a hot interstellar medium (e.g., within a starburst region), and shocks in molecular clouds, where time-dependent chemistry can lead to overstability.

  13. Cholesterol: the debate should be terminated.

    PubMed

    Nathan, David G

    2017-07-01

    Here, I offer personal perspectives on cholesterol homeostasis that reflect my belief that certain aspects of the debate have been overstated.-Nathan, D. G. Cholesterol: the debate should be terminated. © FASEB.

  14. - Fishing Vessels « Coast Guard Maritime Commons

    Science.gov Websites

    be overstated. This post provides resources and tips to help vessel operators reduce the risk of all the relevant Coast Guard information you need. Use the 'submit ideas' tab on the right or post in

  15. Migration of planets into and out of mean motion resonances in protoplanetary discs: analytical theory of second-order resonances

    NASA Astrophysics Data System (ADS)

    Xu, Wenrui; Lai, Dong

    2017-07-01

    Recent observations of Kepler multiplanet systems have revealed a number of systems with planets very close to second-order mean motion resonances (MMRs, with period ratio 1 : 3, 3 : 5, etc.). We present an analytic study of resonance capture and its stability for planets migrating in gaseous discs. Resonance capture requires slow convergent migration of the planets, with sufficiently large eccentricity damping time-scale Te and small pre-resonance eccentricities. We quantify these requirements and find that they can be satisfied for super-Earths under protoplanetary disc conditions. For planets captured into resonance, an equilibrium state can be reached, in which eccentricity excitation due to resonant planet-planet interaction balances eccentricity damping due to planet-disc interaction. This 'captured' equilibrium can be overstable, leading to partial or permanent escape of the planets from the resonance. In general, the stability of the captured state depends on the inner to outer planet mass ratio q = m1/m2 and the ratio of the eccentricity damping times. The overstability growth time is of the order of Te, but can be much larger for systems close to the stability threshold. For low-mass planets undergoing type I (non-gap opening) migration, convergent migration requires q ≲ 1, while the stability of the capture requires q ≳ 1. These results suggest that planet pairs stably captured into second-order MMRs have comparable masses. This is in contrast to first-order MMRs, where a larger parameter space exists for stable resonance capture. We confirm and extend our analytical results with N-body simulations, and show that for overstable capture, the escape time from the MMR can be comparable to the time the planets spend migrating between resonances.

  16. Underestimation of the efficacy, effectiveness, tolerability, and safety of weekly low-dose methotrexate in information presented to physicians and patients.

    PubMed

    Pincus, T; Furer, V; Sokka, T

    2010-01-01

    Ten specific examples of the underestimation of the efficacy, effectiveness and tolerability, and overestimation of adverse events of weekly, low-dose methotrexate, administered with folic acid, in treatment of rheumatic diseases are summarised. These examples include: 1) meta-analyses of clinical trials suggest that methotrexate has an efficacy similar to other disease-modifying anti-rheumatic drugs (DMARDs); 2) information in textbooks and websites may overstate adverse events and drug interactions associated with weekly low-dose methotrexate; 3) information presented to patients when filling a prescription for methotrexate understates 'side effects' of RA and overstates those of methotrexate; 4) an admonition to patients to refrain entirely from consumption of alcohol while taking methotrexate may be unnecessary; 5) frequent blood testing in patients who take methotrexate may be overused; 6) eligibility of only a small minority of patients for clinical trials to compare biologic agents and methotrexate; 7) Step-up design in most comparisons of biologic agents with methotrexate includes only patients who had experienced an incomplete response to methotrexate; 8) in parallel design trials, the efficacy of biologic agents is not substantially greater than that of methotrexate; 9) low, inflexible dosage schedules of methotrexate and requirement for withdrawal with minimal liver function abnormalities in many clinical trials may underestimate efficacy, effectiveness, tolerability and safety; 10) interpretation of clinical trial results may overstate the clinical significance of lower radiographic progression in patients treated with biologic agents versus patients treated with methotrexate. More accurate interpretation of information for physicians and other health professionals, as well as patients, concerning use of weekly low-dose methotrexate in contemporary care could improve care and outcomes for patients with RA and other rheumatic diseases.

  17. Psychology's Atomic Bomb

    ERIC Educational Resources Information Center

    Borsboom, Denny; Wijsen, Lisa D.

    2017-01-01

    The central role of educational testing practices in contemporary societies can hardly be overstated. It is furthermore evident that psychometric models regulate, justify, and legitimize the processes through which educational testing practices are used. In this commentary, the authors offer some observations that may be relevant for the analyses…

  18. Report: Projected Emission Reductions Overstated and Buy American Requirements Not Met Under EPA Award to the Tennessee Department of Transportation

    EPA Pesticide Factsheets

    Report #13-R-0321, July 19, 2013. TDOT followed most applicable laws, regulations, and terms and conditions of the cooperative agreement - with the exception of the Buy American requirements of the Recovery Act.

  19. The GMO-Nanotech (Dis)Analogy?

    ERIC Educational Resources Information Center

    Sandler, Ronald; Kay, W. D.

    2006-01-01

    The genetically-modified-organism (GMO) experience has been prominent in motivating science, industry, and regulatory communities to address the social and ethical dimensions of nanotechnology. However, there are some significant problems with the GMO-nanotech analogy. First, it overstates the likelihood of a GMO-like backlash against…

  20. In Response to Rowland on "Realism and Debateability in Policy Advocacy."

    ERIC Educational Resources Information Center

    Herbeck, Dale A.; Katsulas, John P.

    1986-01-01

    Argues that Robert Rowland has overstated the case against the permutation process for assessing counterplan competitiveness. Claims that the permutation standard is a viable method for ascertaining counterplan competitiveness. Examines Rowland's alternative and argues that it is an unsatisfactory method for determining counterplan…

  1. What Research Does and Doesn't Say about Breastfeeding: A Critical Review

    ERIC Educational Resources Information Center

    Schulze, Pamela A.; Carlisle, Sunny A.

    2010-01-01

    The authors review the research literature on breastfeeding benefits and promotion. Although breastfeeding confers numerous benefits to infants, mothers and society, the authors conclude that breastfeeding promotion efforts sometimes overstate or misrepresent what the research actually supports about the benefits of breastfeeding. Psychological or…

  2. Water yields from forests: an agnostic view

    Treesearch

    Robert R. Ziemer

    1987-01-01

    Abstract - Although experimental watershed studies have consistently shown that water yield can be increased by removing trees and shrubs, programs to increase water yield on an operational scale have consistently failed. Failure has been related to overstated goals and benefits, unrealistic assumptions, political naivete, and the emergence of new interest groups....

  3. Fuelwood Problems and Solutions

    Treesearch

    D. Evan Mercer; John Soussan

    1992-01-01

    Concern over the "fuelwood crisis" facing the world's poor has been widespread since the late 1970s (Eckholm et al. 1984; Soussan 1988; Agarwal 1986). At first the problem was frequently overstated. In the extreme, analysts (foresters, economists, and others) in many countries made erroneous projections of the rapid total destruction of the biomass...

  4. Communication Skills in Medical Education: An Integrated Approach

    ERIC Educational Resources Information Center

    Bennett, Kellie; Lyons, Zaza

    2011-01-01

    The importance of teaching communication skills in any undergraduate medical curriculum cannot be overstated. Effective doctor-patient communication is widely recognised as an essential aspect of quality patient care. A communication skills module developed for first year medical students at the University of Western Australia (UWA) is described…

  5. Communities of Practice and Professional Development

    ERIC Educational Resources Information Center

    Chalmers, Lex; Keown, Paul

    2006-01-01

    The Internet has had a transformative effect on many aspects of contemporary living. While there may be a tendency to overstate the impacts of this technology, workplaces and work practices in many societies have been greatly affected by almost instant access to massive amounts of information, delivered through broadening bandwidth. This paper…

  6. The Limits of Empowerment in Anti-Nuclear Advocacy: A Case Study of Adult Education for Technological Literacy.

    ERIC Educational Resources Information Center

    Regnier, Robert; Penna, Phillip

    1996-01-01

    Using a theory of technological literacy, analysis of a project to oppose uranium mining in Saskatchewan revealed how the potential for empowerment is often overstated. Informing citizens to participate in critical discourse does not always lead to decisions reflecting their interests. (SK)

  7. Education and Primitive Accumulation in Sub-Saharan Africa.

    ERIC Educational Resources Information Center

    Emoungu, Paul-Albert N.

    1992-01-01

    The 1988 World Bank report on education in sub-Saharan Africa overstates the regional "crisis" in educational quality and recommends unrealistic strategies, ignoring the fact that basic human needs such as education are unmet because political elites corruptly privatize much of the wealth generated by their nations' economies. (SV)

  8. Parent and Teacher Satisfaction with School-Based Psychological Reports

    ERIC Educational Resources Information Center

    Rahill, Stephanie A.

    2018-01-01

    School psychologists spend a great deal of time translating assessment results into a psychoeducational report. The importance of creating reports that are both useful and understandable to the readers of the report while also being efficient for the school psychologist cannot be overstated. This study examines parent and teacher perceptions…

  9. Teenage Pregnancy. Opposing Viewpoints Series.

    ERIC Educational Resources Information Center

    Thompson, Stephen P.

    Books in the Opposing Viewpoints series challenge readers to question their own opinions and assumptions. By reading carefully balanced views, readers confront new ideas on the topic of interest. Although some experts believe that the problem of teenage pregnancy has been overstated, other recent studies have led many people to believe that…

  10. Large Scale IR Evaluation

    ERIC Educational Resources Information Center

    Pavlu, Virgil

    2008-01-01

    Today, search engines are embedded into all aspects of digital world: in addition to Internet search, all operating systems have integrated search engines that respond even as you type, even over the network, even on cell phones; therefore the importance of their efficacy and efficiency cannot be overstated. There are many open possibilities for…

  11. An Examination of Pre-Service Agricultural Science Teachers' Interest and Participation in International Experiences: Motivations and Barriers

    ERIC Educational Resources Information Center

    Murphrey, Theresa Pesl; Lane, Katy; Harlin, Julie; Cherry, Audie

    2016-01-01

    The importance of creating global mindedness within pre-service agricultural science teachers through international experiences cannot be overstated. However, providing opportunities for international experiences and college students selecting to participate in these opportunities are two very different actions. Mechanisms must be put in place…

  12. Peer Instruction and Secondary School Students' Achievement in Vectors

    ERIC Educational Resources Information Center

    Ouko, Susan; Aurah, Catherine; Amadalo, Maurice

    2015-01-01

    The importance of raising students' competence in mathematics in a developing country such as Kenya cannot be overstated. This is because to produce professionals in areas such as engineering, medicine and accounting requires a good score in mathematics. Students that will further their studies in these areas will find that vectors is prerequisite…

  13. Nonword Repetition, Phonological Storage, and Multiple Determinations

    ERIC Educational Resources Information Center

    Gupta, Prahlad

    2006-01-01

    The proposals that (a) nonword repetition and word learning both rely on phonological storage and (b) both are multiply determined are two of the major foci of Gathercole's (2006) Keynote Article, which marshals considerable evidence in support of each. In my view, the importance of these proposals cannot be overstated: these two notions go to the…

  14. Chapter 4: Use of fire to manage populations of nonnative invasive plants

    Treesearch

    Peter M. Rice; Jane Kapler Smith

    2008-01-01

    It may be impossible to overstate the complexity of relationships among wildland ecosystems, fires, and nonnative invasives. Strategies for managing these relationships are similarly complex; they require information on local plant phenology, ability to produce various levels of fire severity within burns, willingness to combine fire with other management techniques,...

  15. Comment on "Declining wild salmon populations in relation to parasites from farm salmon".

    PubMed

    Riddell, Brian E; Beamish, Richard J; Richards, Laura J; Candy, John R

    2008-12-19

    Krkosek et al. (Reports, 14 December 2007, p. 1772) claimed that sea lice spread from salmon farms placed wild pink salmon populations "on a trajectory toward rapid local extinction." Their prediction is inconsistent with observed pink salmon returns and overstates the risks from sea lice and salmon farming.

  16. Five Perspectives for Teaching the Holocaust

    ERIC Educational Resources Information Center

    Lindquist, David H.

    2008-01-01

    Studying the Holocaust provides an opportunity to explore a fascinating historical topic whose impact on the contemporary world cannot be overstated. As such, the topic is now an accepted part of the American secondary school curriculum. For such curricula to be of maximum benefit to students, clearly defined perspectives that direct the students'…

  17. Diversity Training. Myths and Realities No. 13.

    ERIC Educational Resources Information Center

    Brown, Bettina Lankard

    Certain myths cause some people to fear or resist diversity training; other myths overstate its outcomes and effectiveness. Many workers--white males in particular--fear that in the rush for a more diverse workplace, they will lose out. Their fears can be addressed by delivering training in a way that convinces employees that the organization's…

  18. Overstated Optimism: Arizona's Structured English Immersion Program under "Horne v. Flores"

    ERIC Educational Resources Information Center

    Mora, Jill Kerper

    2010-01-01

    This article is an analysis of the educational implications of the Supreme Court (USSC) decision in "Horne v. Flores" (2009). The USSC remanded the Arizona case to the lower court, requiring a rehearing of petitioners' request for relief from the court's oversight of AZ's "structured English immersion" (SEI) program mandated…

  19. Investigating Human Evolution Using Digital Imaging & Craniometry

    ERIC Educational Resources Information Center

    Robertson, John C.

    2007-01-01

    Human evolution is an important and intriguing area of biology. The significance of evolution as a component of biology curricula, at all levels, can not be overstated; the need to make the most of opportunities to effectively educate students in evolution as a central and unifying realm of biology is paramount. Developing engaging laboratory or…

  20. Shared Mental Models in Support of Adaptive Instruction for Teams Using the GIFT Tutoring Architecture

    ERIC Educational Resources Information Center

    Fletcher, J. D.; Sottilare, Robert A.

    2018-01-01

    Teams and teamwork are ubiquitous in military and civilian organizations. Their importance to organizational success cannot be overstated. This article describes the relationship and effect of three concepts: Intelligent Tutoring Systems (ITSs), shared mental models, and teamwork. The nexus between these concepts is examined to determine its…

  1. Fusing Classroom Theory and Practical Experience: Syllabus Construction in a Broadcast Journalism Experience.

    ERIC Educational Resources Information Center

    Reppert, James E.

    This paper contends that it is essential that broadcast journalism courses possess a roughly equal balance between hands-on radio, television, and electronic news gathering assignments and analytical term papers. The importance of students writing and analyzing mass communication issues and personalities cannot be overstated in a highly…

  2. Social Networking Practices in School Psychology: Have Moral Panic Concerns Been Overstated?

    ERIC Educational Resources Information Center

    Segool, Natasha K.; Goforth, Anisa N.; Bowman, Nicholas; Pham, Andy

    2016-01-01

    The almost ubiquitous use of Facebook and other social networking sites (SNSs) by adults in the United States raises important practice considerations for school psychologists. This study examined the SNS practices of school psychologists, graduate trainers, and graduate students to explore (a) SNS use training experiences for school…

  3. Class Reproduction among Men and Women in France: Reproduction Theory on Its Home Ground.

    ERIC Educational Resources Information Center

    Robinson, Robert V.; Garnier, Maurice A.

    1985-01-01

    A survey of employed men and women in France showed that French reproduction theory has overstated the role of education in reproducing class advantage from generation to generation. Education serves less as a reproducer of class advantage than as a vehicle of mobility into managerial positions. (Author/RM)

  4. Luther's Antisemitism in Historical Context: A Necessary Discussion for Christian Educators

    ERIC Educational Resources Information Center

    Lindquist, David H.

    2013-01-01

    Martin Luther remains a complex, contradictory figure whose impact on modern Western history cannot be overstated. Among the most controversial aspects of Luther's work is his ambivalent perspective of the Jews. The early Luther viewed the Jews warmly, depicting them as Christianity's historical and religious ancestors. Later, however, he…

  5. Damping of Resonantly Forced Density Waves in Dense Planetary Rings

    NASA Astrophysics Data System (ADS)

    Lehmann, Marius; Schmidt, Jürgen; Salo, Heikki

    2016-10-01

    We address the stability of resonantly forced density waves in dense planetary rings.Already by Goldreich and Tremaine (1978) it has been argued that density waves might be unstable, depending on the relationship between the ring's viscosity and the surface mass density. In the recent paper (Schmidt et al. 2016) we have pointed out that when - within a fluid description of the ring dynamics - the criterion for viscous overstability is satisfied, forced spiral density waves become unstable as well. In this case, linear theory fails to describe the damping.We apply the multiple scale formalism to derive a weakly nonlinear damping relation from a hydrodynamical model.This relation describes the resonant excitation and nonlinear viscous damping of spiral density waves in a vertically integrated fluid disk with density dependent transport coefficients. The model consistently predicts linear instability of density waves in a ring region where the conditions for viscous overstability are met. In this case, sufficiently far away from the Lindblad resonance, the surface mass density perturbation is predicted to saturate to a constant value due to nonlinear viscous damping. In general the model wave damping lengths depend on a set of input parameters, such as the distance to the threshold for viscous overstability and the ground state surface mass density.Our new model compares reasonably well with the streamline model for nonlinear density waves of Borderies et al. 1986.Deviations become substantial in the highly nonlinear regime, corresponding to strong satellite forcing.Nevertheless, we generally observe good or at least qualitative agreement between the wave amplitude profiles of both models. The streamline approach is superior at matching the total wave profile of waves observed in Saturn's rings, while our new damping relation is a comparably handy tool to gain insight in the evolution of the wave amplitude with distance from resonance, and the different regimes of wave formation and the dependence on the parameters of the model.

  6. Three Simple Hands-On Soil Exercises Extension Professionals Can Incorporate into Natural Sciences Curriculum

    ERIC Educational Resources Information Center

    Kleinschmidt, Andy

    2011-01-01

    The importance of healthy soil and of conveying the importance of soils starts by conveying a few basic concepts of soil science cannot be overstated. This article provides three hands-on exercises Extension professionals can add to natural resources or Master Gardener education curricula. These natural sciences exercises are easy to prepare for…

  7. Intelligence and Savant Syndrome: Is the Whole Greater than the Sum of the Fragments?

    ERIC Educational Resources Information Center

    Nettelbeck, Ted; Young, Robyn

    1996-01-01

    It is argued that skills displayed by savants are not intelligent and that H. Gardner's theory of multiple intelligences fails by overstating the relevance of savant skills and because it disregards research evidence for a general factor. Intelligence theory must compile a structure that accounts for savant skills and intelligence. (SLD)

  8. It's Not Always Good For You: Theatre Is Not Supposed To Be Medicine.

    ERIC Educational Resources Information Center

    Gregg, Stephen

    2002-01-01

    Suggests that theatre's capacity to educate is often overstated. Notes theatre created by and for teenagers is especially guilty of proselytizing. Argues the real danger is that the cumulative, subliminal message is that theater is medicine. Suggests that playwrights, directors, and artistic directors leave the education for the classroom and take…

  9. Identifying Leadership Potential: The Process of Principals within a Charter School Network

    ERIC Educational Resources Information Center

    Waidelich, Lynn A.

    2012-01-01

    The importance of strong educational leadership for American K-12 schools cannot be overstated. As such, school districts need to actively recruit and develop leaders. One way to do so is for school officials to become more strategic in leadership identification and development. If contemporary leaders are strategic about whom they identify and…

  10. A Study of Preferred Conflict-Management Behaviors among Small-School Principals: Effects of Gender and Experience

    ERIC Educational Resources Information Center

    Vestal, Brad; Torres, Mario

    2016-01-01

    It cannot be overstated the broad skill set managers must have to manage conflict in modern organizations (Lang, 2009; Ramani & Zhimin, 2010). Few studies have explored this topic in smaller organizational settings where leaders often assume a greater number of roles and responsibilities. For this reason, this study analyzed preferred conflict…

  11. Dynamo: A Model Transition Framework for Dynamic Stability Control and Body Mass Manipulation

    DTIC Science & Technology

    2011-11-01

    driving at high speed, and you turn the steering wheel hard to the right and slam on the brakes, then you will end up in the oversteer regime. At the...sensors (GPS, IMU, LIDAR ) for vehicle control. Figure 17: Dynamo high-speed small UGV hardware platform We will perform experiments to measure the MTC

  12. Teaching Introductory Programming to IS Students: Java Problems and Pitfalls

    ERIC Educational Resources Information Center

    Pendergast, Mark O.

    2006-01-01

    This paper examines the impact the use of the Java programming language has had on the way our students learn to program and the success they achieve. The importance of a properly constructed first course in programming cannot be overstated. A course well experienced will leave students with good programming habits, the ability to learn on their…

  13. 77 FR 38501 - Approval and Promulgation of Implementation Plans; State of Georgia; Regional Haze State...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-28

    ... no additional emissions controls for some pollutants but does not specify an appropriately stringent... controls from examination based on economic factors alone. Response 4: The Commenter overstates the scope... beyond the control of the user (see, e.g., 40 CFR 60.7575; Georgia Air Quality Control Rules 391-3-1-.02...

  14. 38 CFR 6.1 - Misstatement of age.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Misstatement of age. 6.1... GOVERNMENT LIFE INSURANCE Age § 6.1 Misstatement of age. If the age of the insured under a United States... shall be such exact amount as the premium paid would have purchased at the correct age; if overstated...

  15. 38 CFR 8.21 - Misstatement of age.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2013-07-01 2013-07-01 false Misstatement of age. 8.21... INSURANCE Age § 8.21 Misstatement of age. If the age of the insured under a National Service life insurance... amount as the premium paid would have purchased at the correct age; if overstated, the excess of premiums...

  16. 38 CFR 8.21 - Misstatement of age.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2014-07-01 2014-07-01 false Misstatement of age. 8.21... INSURANCE Age § 8.21 Misstatement of age. If the age of the insured under a National Service life insurance... amount as the premium paid would have purchased at the correct age; if overstated, the excess of premiums...

  17. 38 CFR 6.1 - Misstatement of age.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2014-07-01 2014-07-01 false Misstatement of age. 6.1... GOVERNMENT LIFE INSURANCE Age § 6.1 Misstatement of age. If the age of the insured under a United States... shall be such exact amount as the premium paid would have purchased at the correct age; if overstated...

  18. 38 CFR 8.21 - Misstatement of age.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2011-07-01 2011-07-01 false Misstatement of age. 8.21... INSURANCE Age § 8.21 Misstatement of age. If the age of the insured under a National Service life insurance... amount as the premium paid would have purchased at the correct age; if overstated, the excess of premiums...

  19. 38 CFR 6.1 - Misstatement of age.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2013-07-01 2013-07-01 false Misstatement of age. 6.1... GOVERNMENT LIFE INSURANCE Age § 6.1 Misstatement of age. If the age of the insured under a United States... shall be such exact amount as the premium paid would have purchased at the correct age; if overstated...

  20. 38 CFR 6.1 - Misstatement of age.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2011-07-01 2011-07-01 false Misstatement of age. 6.1... GOVERNMENT LIFE INSURANCE Age § 6.1 Misstatement of age. If the age of the insured under a United States... shall be such exact amount as the premium paid would have purchased at the correct age; if overstated...

  1. 38 CFR 6.1 - Misstatement of age.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2012-07-01 2012-07-01 false Misstatement of age. 6.1... GOVERNMENT LIFE INSURANCE Age § 6.1 Misstatement of age. If the age of the insured under a United States... shall be such exact amount as the premium paid would have purchased at the correct age; if overstated...

  2. 38 CFR 8.21 - Misstatement of age.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2012-07-01 2012-07-01 false Misstatement of age. 8.21... INSURANCE Age § 8.21 Misstatement of age. If the age of the insured under a National Service life insurance... amount as the premium paid would have purchased at the correct age; if overstated, the excess of premiums...

  3. 38 CFR 8.21 - Misstatement of age.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Misstatement of age. 8.21... INSURANCE Age § 8.21 Misstatement of age. If the age of the insured under a National Service life insurance... amount as the premium paid would have purchased at the correct age; if overstated, the excess of premiums...

  4. Trade Secret Law and Information Systems: Can Your Students Keep a Secret?

    ERIC Educational Resources Information Center

    Willey, Lorrie; Ford, Janet C.; White, Barbara Jo; Clapper, Danial L.

    2011-01-01

    The impact of intellectual property (IP) law on information systems (IS) professionals in business cannot be overstated. The IS 2010 model curriculum guidelines for undergraduate IS programs stress the importance of information security and knowledge about IP. While copyright and patents are the most well-known types of IP, another, trade secrets,…

  5. Understanding New Jersey's School Funding Formula: The Role of Adjustment Aid

    ERIC Educational Resources Information Center

    Farrie, Danielle; Luhm, Theresa; Johnson, Monete

    2015-01-01

    The objective of this policy brief is to explain the purpose of adjustment aid in New Jersey's school funding formula and to correct several misconceptions about the level of aid and how it is distributed. The main conclusions include: (1) The amount of adjustment aid in the funding formula is currently overstated in the "informational"…

  6. Homosexual Subject(ivitie)s in Music (Education): Deconstructions of the Disappeared

    ERIC Educational Resources Information Center

    Gould, Elizabeth

    2012-01-01

    It is difficult to overstate music's persistent and uneasy relationship with homosexuality in Western society. Associated with femininity for centuries, particularly in North America, participation in music has been believed to emasculate and thus homosexualize men and boys. The linking of music to women and emotion (as opposed to men and reason)…

  7. Alcohol and Tobacco Counter-Ads: Stealing a Page from Billboard Utilizing Graffitists against Unhealthy Promotions

    ERIC Educational Resources Information Center

    Hall, P. Cougar; Lindsay, Gordon B.; West, Joshua H.

    2011-01-01

    The influence of media on adolescents' health practices and behaviors, including personal values, beliefs, and perceived norms cannot be overstated. Youth media consumption continues to increase. Media messages are carefully designed to persuade the consumer to believe or do something. Some of the most persuasive media messages can be found in…

  8. Is There a Correlation between US University Presidential Pay and Performance?

    ERIC Educational Resources Information Center

    Risler, Laura; Harrison, Laura M.

    2014-01-01

    This paper scrutinises the escalating salaries of US college and university presidents (vice-chancellors, or rectors, as they might be known in other parts of the world). Some research suggests that presidential pay is largely correlated with factors that have little or nothing to do with performance and may, therefore, overstate the benefit that…

  9. The Pedagogy of Ingenuity in Science: An Exploration of Creative Thinking in the Secondary Science Classroom

    ERIC Educational Resources Information Center

    Antink, Allison

    2012-01-01

    The importance of creative thinking in science cannot be overstated. Creativity is integral to the development of knowledge about the natural world and the knowledge, skills and abilities that support it are in need of greater understanding. The Next Generation Science Standards (2012) include practices that implicitly emphasize the creative…

  10. A Microscope or a Mirror?: A Question of Study Validity Regarding the Use of Dissertation Citation Analysis for Evaluating Research Collections

    ERIC Educational Resources Information Center

    Beile, Penny M.; Boote, David N.; Killingsworth, Elizabeth K.

    2004-01-01

    Use of dissertation citation analysis for collection evaluation was investigated. Analysis of 1842 education dissertation citations from three institutions suggests the assumption of doctoral student expertise in their use of the scholarly literature may be overstated. For purposes of developing research collections, dependence on dissertation…

  11. International Social Work: A Situational Analysis of Accredited CSWE Institutions in Mid-Western USA

    ERIC Educational Resources Information Center

    Lamin, Sylvester Amara

    2012-01-01

    The importance of International social work education these days cannot be overstated as social work has been established in nearly every part of the world. Also, globalization has been pivotal as it has facilitated the movement of people, improved technology and other social problems as well. American higher education is challenged to expand and…

  12. Evaluation of the Challenges in the Implementation of the Guidance and Counselling Programme in Baringo County Secondary Schools, Kenya

    ERIC Educational Resources Information Center

    Boitt, Monicah Lydia. J.

    2016-01-01

    The need for guidance and counselling services in all learning institutions cannot be overstated. In response to this demand, guidance and counselling programme has been implemented since 1971 and more emphasis on its services in 2001 through Legal Notice, No. 95 of the Kenya Gazette that recommended guidance and counseling departments be…

  13. Embracing the Potential of Play for Children on the Autism Spectrum: Facilitating the Earliest Stages of Developmental Integration

    ERIC Educational Resources Information Center

    Gerber, Sima

    2017-01-01

    In this article, the breadth and depth of play as an integrating process for children with developmental challenges are explored. The fact that play is a source of developmental growth suggests that its role in intervention with children with language and communication disorders cannot be overstated. Several contemporary play-based intervention…

  14. Exploring Prosocial Behavior through Structured Philosophical Dialogue: A Quantitative Evaluation

    ERIC Educational Resources Information Center

    Glina, Monica B.

    2015-01-01

    The problem of bullying in schools cannot be overstated. Researchers have examined the problem of bullying in schools from a variety of perspectives and have found that bullying has serious short-and long-term effects not just for the victim but for the bully as well. A variety of interventions have been implemented, and research shows that the…

  15. Hmong in America. Journey from a Secret War.

    ERIC Educational Resources Information Center

    Pfaff, Tim

    Since 1975, the United States has accepted more than 110,000 Laotian highlanders as refugees, the vast majority of whom are Hmong. The Hmong in America trace their Chinese ancestry back thousands of years, but their recent history is rooted in Laos where Hmong families escaped from China in the mid-1800s. It is difficult to overstate the culture…

  16. Addressing Ethics and Technology in Business: Preparing Today's Students for the Ethical Challenges Presented by Technology in the Workplace

    ERIC Educational Resources Information Center

    Brooks, Rochelle

    2008-01-01

    The ethical development of information systems is but one of those sensitive scenarios associated with computer technology that has a tremendous impact on individuals and social life. The significance of these issues of concern cannot be overstated. However, since computer ethics is meant to be everybody's responsibility, the result can often be…

  17. Additional Evidence Is Needed to Recommend Acquiring a Dog to Families of Children with Autism Spectrum Disorder: A Response to Wright and Colleagues

    ERIC Educational Resources Information Center

    Crossman, Molly K.; Kazdin, Alan E.

    2016-01-01

    Caregivers of children with autism spectrum disorder are vulnerable to overstated benefits of interventions, and such overstatements are common with interventions involving animals. This response to Wright, Hall, Hames, Hardmin, Mills, the Paws Team, and Mills' (2015) article, "Acquiring a Pet Dog Significantly Reduces Stress of Primary…

  18. Information asymmetry and deception.

    PubMed

    Clots-Figueras, Irma; Hernán-González, Roberto; Kujal, Praveen

    2015-01-01

    Situations such as an entrepreneur overstating a project's value, or a superior choosing to under or overstate the gains from a project to a subordinate are common and may result in acts of deception. In this paper we modify the standard investment game in the economics literature to study the nature of deception. In this game a trustor (investor) can send a given amount of money to a trustee (or investee). The amount received is multiplied by a certain amount, k, and the investee then decides on how to divide the total amount received. In our modified game the information on the multiplier, k, is known only to the investee and she can send a non-binding message to the investor regarding its value. We find that 66% of the investees send false messages with both under and over, statement being observed. Investors are naive and almost half of them believe the message received. We find greater lying when the distribution of the multiplier is unknown by the investors than when they know the distribution. Further, messages make beliefs about the multiplier more pessimistic when the investors know the distribution of the multiplier, while the opposite is true when they do not know the distribution.

  19. Failure of physicians to recognize functional disability in ambulatory patients.

    PubMed

    Calkins, D R; Rubenstein, L V; Cleary, P D; Davies, A R; Jette, A M; Fink, A; Kosecoff, J; Young, R T; Brook, R H; Delbanco, T L

    1991-03-15

    To assess the ability of internists to identify functional disabilities reported by their patients. Comparison of responses by physicians and a random sample of their patients to a 12-item questionnaire about physical and social function. A hospital-based internal medicine group practice in Boston, Massachusetts, and selected office-based internal medicine practices in Los Angeles, California. Five staff physicians, three general internal medicine fellows, and 34 internal medicine residents in the hospital-based practice and 178 of their patients. Seventy-six physicians in the office-based practices and 230 of their patients. Physicians underestimated or failed to recognize 66% of disabilities reported by patients. Patient-reported disabilities were underestimated or unrecognized more often in the hospital-based practice than in the office-based practices (75% compared with 60%, P less than 0.05). Physicians overstated functional impairment in 21% of paired responses in which patients reported no disability. Physicians often underestimate or fail to recognize functional disabilities that are reported by their patients. They overstate functional impairment to a lesser degree. Because these discrepancies may adversely affect patient care and well-being, medical educators and clinicians should pay more attention to the assessment of patient function.

  20. Information asymmetry and deception

    PubMed Central

    Clots-Figueras, Irma; Hernán-González, Roberto; Kujal, Praveen

    2015-01-01

    Situations such as an entrepreneur overstating a project's value, or a superior choosing to under or overstate the gains from a project to a subordinate are common and may result in acts of deception. In this paper we modify the standard investment game in the economics literature to study the nature of deception. In this game a trustor (investor) can send a given amount of money to a trustee (or investee). The amount received is multiplied by a certain amount, k, and the investee then decides on how to divide the total amount received. In our modified game the information on the multiplier, k, is known only to the investee and she can send a non-binding message to the investor regarding its value. We find that 66% of the investees send false messages with both under and over, statement being observed. Investors are naive and almost half of them believe the message received. We find greater lying when the distribution of the multiplier is unknown by the investors than when they know the distribution. Further, messages make beliefs about the multiplier more pessimistic when the investors know the distribution of the multiplier, while the opposite is true when they do not know the distribution. PMID:26257615

  1. The Selection of Gifted Students: Did Malcolm Gladwell Overstate the Role of Relative Age in the Gifted Program Selection Process?

    ERIC Educational Resources Information Center

    O'Reilly, Frances L.; Matt, John J.

    2012-01-01

    Both gifted educators and parents need to be vigilant as to how gifted education is characterized in the popular media. Gifted educators spend countless resources to meet the needs of gifted students using very limited fiscal resources, and it is imperative that those efforts are not undermined in the popular media by unsubstantiated statements.…

  2. An isoline separating relatively warm from relatively cool wintertime forest surface temperatures for the southeastern United States

    Treesearch

    J. Wickham; T.G. Wade; K.H. Riitters

    2014-01-01

    Forest-oriented climate mitigation policies promote forestation as a means to increase uptake of atmospheric carbon to counteract global warming. Some have pointed out that a carbon-centric forest policy may be overstated because it discounts biophysical aspects of the influence of forests on climate. In extra-tropical regions, many climate models have shown that...

  3. Testing key predictions of the associative account of mirror neurons in humans using multivariate pattern analysis.

    PubMed

    Oosterhof, Nikolaas N; Wiggett, Alison J; Cross, Emily S

    2014-04-01

    Cook et al. overstate the evidence supporting their associative account of mirror neurons in humans: most studies do not address a key property, action-specificity that generalizes across the visual and motor domains. Multivariate pattern analysis (MVPA) of neuroimaging data can address this concern, and we illustrate how MVPA can be used to test key predictions of their account.

  4. Perspectives on Research in Artificial Intelligence and Artificial General Intelligence Relevant to DoD

    DTIC Science & Technology

    2017-01-01

    3.2 Generic Network Architecture ........................................................................................ 11 3.3 Neuron Non ...The magnitude of the importance of these technologies is hard to overstate, and we thus feel that technically minded, non -expert readers should be...The result is often billions of weights and biases which need to be calculated. 13 3.3 Neuron Non -Linearity The big, early advance in

  5. Hamlet without the Prince: Shortcomings of an Activity-Based Account of Joint Attention

    ERIC Educational Resources Information Center

    Hobson, R. Peter

    2007-01-01

    In this commentary, I consider several strengths of the position adopted by Racine and Carpendale (2007), but suggest that the authors are in danger of overstating their case. In doing so, they appear to sideline an issue that should be pivotal for accounts of joint attention: how does a child come to arrive at an understanding that people, both…

  6. A modified Plasmodium falciparum growth inhibition assay (GIA) to assess activity of plasma from malaria endemic areas.

    PubMed

    Mlambo, Godfree; Kumar, Nirbhay

    2007-02-01

    Plasma samples from patients undergoing treatment in malaria endemic countries often contain anti-malaria drugs, that may overstate effects of specific antibodies in growth inhibition assays (GIA). We describe a modified assay that uses drug resistant P. falciparum parasites (W2) that circumvents the requirement for dialyzing samples that may likely contain drugs such as chloroquine and sulfadoxine/pyrimethamine (SP).

  7. Childhood in Crisis? Perceptions of 7-11-Year-Olds on Being a Child and the Implications for Education's Well-Being Agenda

    ERIC Educational Resources Information Center

    Adams, Kate

    2013-01-01

    Notions of a good childhood are inextricably linked with well-being. Both concepts are central to a contentious debate about the quality of childhood in the UK, which is partly situated within the "childhood in crisis" discourse which opponents claim is overstated. This study contributes to the debate by hearing the voices of children as…

  8. Air & Space Power Journal. Volume 29, Number 3, May-June 2015

    DTIC Science & Technology

    2015-06-01

    directed-energy beams, radio - frequency strikes, and acoustic weapons, among others.9 One can hardly overstate the impact of cyber, drones, and even newer...showcased the superiority of free societies over their totalitarian counterparts. Not surprisingly, once the Apollo 11 mission fulfilled President...PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR’S ACRONYM(S) 11 . SPONSOR/MONITOR’S REPORT

  9. Implementing SFAS No 121: Accounting for Impaired Assets.

    PubMed

    Luecke, R W; Meeting, D T; Stotzer, W G

    1996-10-01

    In March 1995, FASB issued Statement of Financial Accounting Standards (SFAS) No. 121: "Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to be Disposed Of." It establishes accounting standards for assets whose carrying costs have been overstated due to a variety of circumstances that have reduced the value of the assets. Healthcare financial managers should fully understand the statement's implications for their organizations.

  10. The Roots of Separate and Unequal: The Virginia and West Virginia Heritage--17th to 20th Century.

    ERIC Educational Resources Information Center

    Higginbotham, A. Leon

    Analyses of the Brown decision often overstate its importance. For centuries before it was handed down, white Americans regarded blacks as inferior. During the time of slavery, white men (including those of apparent stature, such as Jefferson and Lincoln) felt that for some reason society could do to black people that which it could not do to any…

  11. The Effect of Convective Overstability on Planet Disk Interactions

    NASA Astrophysics Data System (ADS)

    Klahr, Hubert; Gomes, Aiara Lobo

    2016-10-01

    We run global two dimensional hydrodynamical simulations, using the PLUTO code and the planet-disk model of Uribe et al. 2011, to investigate the effect of the convective overstability (CO) on planet-disk interactions. First, we study the long-term evolution of planet-induced vortices. We found that the CO leads to smoother planetary gap edges, thus weaker planet-induced vortices. The main result was the observation of two generation of vortices, which can pose an explanation for the location of the vortex in the Oph IRS48 system. The lifetime of the primary vortices, as well as the birth time of the secondary vortices are shown to be highly dependent on the thermal relaxation timescale. Second, we study the long-term evolution of the migration of low mass planets and assess whether the CO can prevent the saturation of the horseshoe drag. We found that the disk parameters that favour slow inward or outward migration oppose the amplification of vortices, meaning that the CO does not seem to be a good mechanism to prevent the saturation of the horseshoe drag. On the other hand, we observed a planetary trap, caused by vortices formed in the horseshoe region. This trap may be an alternative mechanism to prevent the fast type I migration rates.

  12. Veterans Affairs: Data Needed to Help Improve Decisions Concerning Veterans’ Access to Burial Options

    DTIC Science & Technology

    2014-09-01

    Comparison of Veteran Population Estimates for Humboldt County Using Proportional Distribution at the County Level and Census Tract Data 20 Figure 7...also areas where this methodology would overstate the veteran population that would be served in a specific area. For example, in Humboldt County...Veterans Cemeteries Figure 6: Comparison of Veteran Population Estimates for Humboldt County Using Proportional Distribution at the County Level and

  13. United States Foreign Policy in Africa: A Right Approach

    DTIC Science & Technology

    1990-04-01

    a higher cost : Except for two of the platinum group metals (platinum and rhodium), andalusite, and a, specific type of industrial diamornd and grade...Defense Department officials, albeit at a higher cost . The Bureau of Mines report in 1988 estimated the 5-year cumulative direct economic cost of a US...the report understated the economic costs and overstated the ability of other mineral- producing nations to replace South African exports.7 Presently

  14. Reply to “Comment on ‘Optically pumped spin-exchange polarized-electron source’ ”

    DOE PAGES

    Pirbhai, M.; Knepper, J.; Litaker, E. T.; ...

    2015-05-26

    In the proceeding Comment [1] on our recent report of a Rb spin-exchange polarized-electron source [2], Williams et al. contend: (a) that our source is poorly characterized compared with modern GaAs sources, (b) that we have overstated the difficulties of using GaAs photoemission sources, and (c) that our explanation of various physics issues related to the source's operating principles are not cogent.

  15. A caution to Native American institutional review boards about scientism and censorship.

    PubMed

    Askland, Andrew

    2002-01-01

    Native American Institutional Review Boards (IRBs) promote the health and welfare of tribes by reviewing protocols for research studies that focus on their tribes. The benefits of approved protocols should not be overstated lest good studies disappoint because they do not satisfy unachievable expectations. IRBs also should avoid the temptation to censor the outcomes of those studies. Science relies on candor and clarity about results and methods to move forward.

  16. Domestic Determinants and Security Policy-Making in East Asia

    DTIC Science & Technology

    2000-11-01

    the U.S.-Japan alliance cannot be overstated as a foundation stone of Asia’s stability, the bilateral relationship has been sub- jected to heavy stress...financial crisis, are addressed by only a single department or ministry. ■ American neglect and Japanese obsession — With the purpose of the alliance ...requirement for a new rationale, fears weakening of American resolve to remain committed. Security independence by Japan and U.S. abandonment of the alliance

  17. Battle on the Bookshelves: History, Desert Storm, and the United States Armed Forces

    DTIC Science & Technology

    2004-06-17

    impacted on the outcome of the war, ranging from superior American technology to flagging Iraqi morale, each of the armed services is free to claim...though decidedly more subtle, could 5 have an equally large impact at the strategic level. For instance, if a service succeeds in overstating its...official accounts of a campaign. Therefore, as part o this work, it is necessary to determine the impact of organizational culture on the observed

  18. Economics of Pharmacogenetic-Guided Treatments: Underwhelming or Overstated?

    PubMed

    Hughes, Dyfrig A

    2018-05-01

    Economic evaluations have dispelled a perception that precision medicine, achieved through pharmacogenetic testing, reduces healthcare costs. For many tests aimed at preventing adverse drug reactions, cost-effectiveness analyses predict modest improvements in health benefits and increases in total costs. While there are many uncertainties in estimating the value of testing, factors that influence cost-effectiveness include the rarity of the outcome, the effectiveness of alternative treatments, and the scope and perspective of analysis. © 2018 ASCPT.

  19. Work-Home Conflict: A Study of the Impact of Role Conflict on U.S. Air Force Company Grade Officer Turnover Intentions

    DTIC Science & Technology

    2007-03-01

    with its envisioned end strength, research (Dalton, Todor , & Krackhardt, 1982) indicates that the voluntary turnover of personnel will have an...evaluated, may be argued to be good for the organization (Dalton, Todor & Krackhardt, 1982). However, dysfunctional voluntary turnover, the voluntary...study of gender differences. Accounting Horizons, 7, 29-38. 117 Dalton, D.R., Todor , W.D., & Krackhardt, D.M. (1982). Turnover overstated: The

  20. Family Annualized Cost of Leaving: The Household as the Decision Unit in Military Retention

    DTIC Science & Technology

    1990-05-01

    the equation shown in the text. Note that the advantage of this approach is that the family is "on" its demand curve for leisure or non... the nonmember spouse while the family remains in the Army, HA. It is the spouse’s labor supply equation and is a function of the spouse’s market wage...typically, overstate losses because it ignores the spouse’s value

  1. An Evaluation of Formate as an Electron Donor to Facilitate Palladium (PD) - Catalyzed Destruction of Chlorinated Aliphatic Hydrocarbons

    DTIC Science & Technology

    2004-03-01

    al. (1985) reported that the capability for central nervous system depression and liver or kidney injury increases with degree of chlorination...skin irritation, and potential liver or kidney damage (Hathaway et al., 1996). The risk for exposure to groundwater contaminated with a CAH 13 is...oxidative metabolites have caused liver and lung tumors in mice, though it appears that direct extrapolation from rodent data would overstate human TCE

  2. The long locum: health propaganda in New Zealand.

    PubMed

    Dow, Derek

    2003-03-14

    Health Department folklore since the 1950s has attributed the rise of health education in New Zealand almost entirely to the efforts of one man, 'Radio Doctor' Harold Turbott. The historical evidence reveals, however, a more extensive commitment by the Health Department, dating back to its foundation in 1900. This paper examines the evolution of health education in New Zealand and concludes that Turbott's role in its development has been overstated, largely at his own instigation.

  3. West German Military Modernization Goals, Resources, and Conventional Arms Control

    DTIC Science & Technology

    1991-01-01

    34 sponsored by the U.S. Air Force’s Deputy Chief of Staff for Plans and Operations. These projects were performed jointly under the National Security Studies...aggregate German defense budgets under a first-stage CFE agreement are assumed to remain flat in real terms. (This probably overstates budget levels... under CFE assumptions. A CFE agreement reduces defense budget shortfalls from 19 percent (the estimated middle-case figure in the absence of arms

  4. Improving DLA Aviation Engineering’s Support to its Customers and the DoD Supply Chain

    DTIC Science & Technology

    2014-10-01

    costs and first article test costs) and (2) DLA supply chain responsiveness as measured in terms of the days required to satisfy unfilled orders ( UFOs ...135,000 UFOs or requisitions at any time. This number of UFOs overstates the magnitude of the backorder problem since many of these backorders are...backorders or long term unfilled orders ( UFOs ). This can have serious implications for the materiel readiness of those weapon systems that utilize

  5. Temporal distributions of crime and disorder in casino and non-casino zones.

    PubMed

    Barthe, Emmanuel; Stitt, B Grant

    2009-06-01

    Research on the relationship between casinos and crime has yielded mixed conclusions. Some authors argue that casinos are crime attractors and provide fertile grounds for disorder in the surrounding communities. Others claim that the impact of casinos on the crime problem has been over-stated and that casinos in themselves are not crime generators. Relying on calls for service and incidents known to the police, this research reveals the specific spatial and temporal characteristics of all criminal and disorderly behaviors around casino venues.

  6. Inadequate Internal Controls Affect Quality and Reliability of the Civil Service Retirement System’s Annual Report.

    DTIC Science & Technology

    1982-10-22

    computation of yearend accruals were not detected. These errors occurred in the computation of: --The net change in the fair value of invest- ments. The...plan administrator made several errors when computing ac- ::ruals for the net change in fair value of investments, interest receivable, and annuity...value of investment securities instead of actual cost in computing the net change in the fair value of investments. The net change was overstated by

  7. Overstating values: medical facts, diverse values, bioethics and values-based medicine.

    PubMed

    Parker, Malcolm

    2013-02-01

    Fulford has argued that (1) the medical concepts illness, disease and dysfunction are inescapably evaluative terms, (2) illness is conceptually prior to disease, and (3) a model conforming to (2) has greater explanatory power and practical utility than the conventional value-free medical model. This 'reverse' model employs Hare's distinction between description and evaluation, and the sliding relationship between descriptive and evaluative meaning. Fulford's derivative 'Values Based Medicine' (VBM) readjusts the imbalance between the predominance of facts over values in medicine. VBM allegedly responds to the increased choices made available by, inter alia, the progress of medical science itself. VBM attributes appropriate status to evaluative meaning, where strong consensus about descriptive meaning is lacking. According to Fulford, quasi-legal bioethics, while it can be retained as a kind of deliberative framework, is outcome-based and pursues 'the right answer', while VBM approximates a democratic, process-oriented method for dealing with diverse values, in partnership with necessary contributions from evidence-based medicine (EBM). I support the non-cognitivist underpinnings of VBM, and its emphasis on the importance of values in medicine. But VBM overstates the complexity and diversity of values, misrepresents EBM and VBM as responses to scientific and evaluative complexity, and mistakenly depicts 'quasi-legal bioethics' as a space of settled descriptive meaning. Bioethical reasoning can expose strategies that attempt to reduce authentic values to scientific facts, illustrating that VBM provides no advantage over bioethics in delineating the connections between facts and values in medicine. © 2011 Blackwell Publishing Ltd.

  8. Interpretation of correlations in clinical research.

    PubMed

    Hung, Man; Bounsanga, Jerry; Voss, Maren Wright

    2017-11-01

    Critically analyzing research is a key skill in evidence-based practice and requires knowledge of research methods, results interpretation, and applications, all of which rely on a foundation based in statistics. Evidence-based practice makes high demands on trained medical professionals to interpret an ever-expanding array of research evidence. As clinical training emphasizes medical care rather than statistics, it is useful to review the basics of statistical methods and what they mean for interpreting clinical studies. We reviewed the basic concepts of correlational associations, violations of normality, unobserved variable bias, sample size, and alpha inflation. The foundations of causal inference were discussed and sound statistical analyses were examined. We discuss four ways in which correlational analysis is misused, including causal inference overreach, over-reliance on significance, alpha inflation, and sample size bias. Recent published studies in the medical field provide evidence of causal assertion overreach drawn from correlational findings. The findings present a primer on the assumptions and nature of correlational methods of analysis and urge clinicians to exercise appropriate caution as they critically analyze the evidence before them and evaluate evidence that supports practice. Critically analyzing new evidence requires statistical knowledge in addition to clinical knowledge. Studies can overstate relationships, expressing causal assertions when only correlational evidence is available. Failure to account for the effect of sample size in the analyses tends to overstate the importance of predictive variables. It is important not to overemphasize the statistical significance without consideration of effect size and whether differences could be considered clinically meaningful.

  9. Zonal flow evolution and overstability in accretion discs

    NASA Astrophysics Data System (ADS)

    Vanon, R.; Ogilvie, G. I.

    2017-04-01

    This work presents a linear analytical calculation on the stability and evolution of a compressible, viscous self-gravitating (SG) Keplerian disc with both horizontal thermal diffusion and a constant cooling time-scale when an axisymmetric structure is present and freely evolving. The calculation makes use of the shearing sheet model and is carried out for a range of cooling times. Although the solutions to the inviscid problem with no cooling or diffusion are well known, it is non-trivial to predict the effect caused by the introduction of cooling and of small diffusivities; this work focuses on perturbations of intermediate wavelengths, therefore representing an extension to the classical stability analysis on thermal and viscous instabilities. For density wave modes, the analysis can be simplified by means of a regular perturbation analysis; considering both shear and thermal diffusivities, the system is found to be overstable for intermediate and long wavelengths for values of the Toomre parameter Q ≲ 2; a non-SG instability is also detected for wavelengths ≳18H, where H is the disc scale-height, as long as γ ≲ 1.305. The regular perturbation analysis does not, however, hold for the entropy and potential vorticity slow modes as their ideal growth rates are degenerate. To understand their evolution, equations for the axisymmetric structure's amplitudes in these two quantities are analytically derived and their instability regions obtained. The instability appears boosted by increasing the value of the adiabatic index and of the Prandtl number, while it is quenched by efficient cooling.

  10. Overstable librations can account for the paucity of mean motion resonances among exoplanet pairs

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Goldreich, Peter; Schlichting, Hilke E., E-mail: pmg@ias.edu, E-mail: hilke@mit.edu

    2014-02-01

    We assess the multi-planet systems discovered by the Kepler satellite in terms of current ideas about orbital migration and eccentricity damping due to planet-disk interactions. Our primary focus is on first order mean motion resonances, which we investigate analytically to lowest order in eccentricity. Only a few percent of planet pairs are in close proximity to a resonance. However, predicted migration rates (parameterized by τ{sub n}=n/| n-dot |) imply that during convergent migration most planets would have been captured into first order resonances. Eccentricity damping (parameterized by τ{sub e}=e/| e-dot |) offers a plausible resolution. Estimates suggest τ {sub e}/τmore » {sub n} ∼ (h/a){sup 2} ∼ 10{sup –2}, where h/a is the ratio of disk thickness to radius. Together, eccentricity damping and orbital migration give rise to an equilibrium eccentricity, e {sub eq} ∼ (τ {sub e}/τ {sub n}){sup 1/2}. Capture is permanent provided e {sub eq} ≲ μ{sup 1/3}, where μ denotes the planet to star mass ratio. But for e {sub eq} ≳ μ{sup 1/3}, capture is only temporary because librations around equilibrium are overstable and lead to passage through resonance on timescale τ {sub e}. Most Kepler planet pairs have e {sub eq} > μ{sup 1/3}. Since τ {sub n} >> τ {sub e} is the timescale for migration between neighboring resonances, only a modest percentage of pairs end up trapped in resonances after the disk disappears. Thus the paucity of resonances among Kepler pairs should not be taken as evidence for in situ planet formation or the disruptive effects of disk turbulence. Planet pairs close to a mean motion resonance typically exhibit period ratios 1%-2% larger than those for exact resonance. The direction of this shift undoubtedly reflects the same asymmetry that requires convergent migration for resonance capture. Permanent resonance capture at these separations from exact resonance would demand μ(τ {sub n}/τ {sub e}){sup 1/2} ≳ 0.01, a value that estimates of μ from transit data and (τ {sub e}/τ {sub n}){sup 1/2} from theory are insufficient to match. Plausible alternatives involve eccentricity damping during or after disk dispersal. The overstability referred to above has applications beyond those considered in this investigation. It was discovered numerically by Meyer and Wisdom in their study of the tidal evolution of Saturn's satellites.« less

  11. Mitigating climate change through managing constructed-microbial communities in agriculture

    DOE PAGES

    Hamilton, Cyd E.; Bever, James D.; Labbe, Jessy; ...

    2015-10-27

    The importance of increasing crop production while reducing resource inputs and land-use change cannot be overstated especially in light of climate change and a human population growth projected to reach nine billion this century. Here, mutualistic plant microbe interactions offer a novel approach to enhance agricultural productivity while reducing environmental costs. In concert with other novel agronomic technologies and management, plant-microbial mutualisms could help increase crop production and reduce yield losses by improving resistance and/or resilience to edaphic, biologic, and climatic variability from both bottom-up and top-down perspectives.

  12. Mitigating climate change through managing constructed-microbial communities in agriculture

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hamilton, Cyd E.; Bever, James D.; Labbe, Jessy

    The importance of increasing crop production while reducing resource inputs and land-use change cannot be overstated especially in light of climate change and a human population growth projected to reach nine billion this century. Here, mutualistic plant microbe interactions offer a novel approach to enhance agricultural productivity while reducing environmental costs. In concert with other novel agronomic technologies and management, plant-microbial mutualisms could help increase crop production and reduce yield losses by improving resistance and/or resilience to edaphic, biologic, and climatic variability from both bottom-up and top-down perspectives.

  13. A Cross-Sectional Investigation of the Effects of Regional Labor Market Conditions on the Reenlistment Decisions of Air Force Enlistees

    DTIC Science & Technology

    1991-09-01

    Baldwin, Robert H. and Thomas V. Daula. "Army Recruit Attrition and Force Manning Costs: Methodology and Analysis," Research in Labor Economics , ed. Ronald...Methodological Issues and a Proposed Specification," Research in Labor Economics , ed. Ronald Ehrenberg, 7:339-363 (1985b). Baldwin, Robert H. et al. "Military...Manpower Research: An Introduction," Research in Labor Economics , ed. Ronald Ehrenberg, L:257-260 (1985). Dalton, Dan R. et al. "Turnover Overstated: The

  14. The proportionate value of proportionality in palliative sedation.

    PubMed

    Berger, Jeffrey T

    2014-01-01

    Proportionality, as it pertains to palliative sedation, is the notion that sedation should be induced at the lowest degree effective for symptom control, so that the patient's consciousness may be preserved. The pursuit of proportionality in palliative sedation is a widely accepted imperative advocated in position statements and guidelines on this treatment. The priority assigned to the pursuit of proportionality, and the extent to which it is relevant for patients who qualify for palliative sedation, have been overstated. Copyright 2014 The Journal of Clinical Ethics. All rights reserved.

  15. The equine practitioner-farrier relationship: building a partnership.

    PubMed

    Moyer, William; O'Grady, Stephen E; Werner, Harry W

    2012-04-01

    The importance of hoof care in maintaining the health and soundness of a horse cannot be overstated. The aphorism, “No foot, no horse” still holds true. For equine ambulatory practitioners, the time devoted to a thorough understanding of the equine digit and it’s care is well worth the investment. The effort devoted to developing good relationships with individuals who will likely be responsible for implementing the changes suggested as a result of that understanding will be rewarded many times over in the course of the equine ambulatory practitioner’s career.

  16. IRS’ Budget Request for Fiscal Year 1992 and Status of the 1991 Tax Return Filing Season

    DTIC Science & Technology

    1991-03-20

    overstated deductions. By not checking delinquent returnis, tie may be giving nonfilers reaon to believe that they can cheat :Wr &d "oi mak Erjammatn...preparing the fiscal year 1991 budget, we told the Subcommittee last year that the prospects for an improved fiscal condition in 1991 appeared good . We...percent of the calls at the same time last year. Returns processing As of March 9P 1991. according to various IRS indicators, IRS has done a good job

  17. Application of Ruze Equation for Inflatable Aperture Antennas

    NASA Technical Reports Server (NTRS)

    Welch, Bryan W.

    2008-01-01

    Inflatable aperture reflector antennas are an emerging technology that NASA is investigating for potential uses in science and exploration missions. As inflatable aperture antennas have not been proven fully qualified for space missions, they must be characterized properly so that the behavior of the antennas can be known in advance. To properly characterize the inflatable aperture antenna, testing must be performed in a relevant environment, such as a vacuum chamber. Since the capability of having a radiofrequency (RF) test facility inside a vacuum chamber did not exist at NASA Glenn Research Center, a different methodology had to be utilized. The proposal to test an inflatable aperture antenna in a vacuum chamber entailed performing a photogrammetry study of the antenna surface by using laser ranging measurements. A root-mean-square (rms) error term was derived from the photogrammetry study to calculate the antenna surface loss as described by the Ruze equation. However, initial testing showed that problems existed in using the Ruze equation to calculate the loss due to errors on the antenna surface. This study utilized RF measurements obtained in a near-field antenna range and photogrammetry data taken from a laser range scanner to compare the expected performance of the test antenna (via the Ruze equation) with the actual RF patterns and directivity measurements. Results showed that the Ruze equation overstated the degradation in the directivity calculation. Therefore, when the photogrammetry study is performed on the test antennas in the vacuum chamber, a more complex equation must be used in light of the fact that the Ruze theory overstates the loss in directivity for inflatable aperture reflector antennas.

  18. Thermal convection in a magnetized conducting fluid with the Cattaneo–Christov heat-flow model

    PubMed Central

    2016-01-01

    By substituting the Cattaneo–Christov heat-flow model for the more usual parabolic Fourier law, we consider the impact of hyperbolic heat-flow effects on thermal convection in the classic problem of a magnetized conducting fluid layer heated from below. For stationary convection, the system is equivalent to that studied by Chandrasekhar (Hydrodynamic and Hydromagnetic Stability, 1961), and with free boundary conditions we recover the classical critical Rayleigh number Rc(c)(Q) which exhibits inhibition of convection by the field according to Rc(c)→π2Q as Q→∞, where Q is the Chandrasekhar number. However, for oscillatory convection we find that the critical Rayleigh number Rc(o)(Q,P1,P2,C) is given by a more complicated function of the thermal Prandtl number P1, magnetic Prandtl number P2 and Cattaneo number C. To elucidate features of this dependence, we neglect P2 (in which case overstability would be classically forbidden), and thereby obtain an expression for the Rayleigh number that is far less strongly inhibited by the field, with limiting behaviour Rc(o)→πQ/C, as Q→∞. One consequence of this weaker dependence is that onset of instability occurs as overstability provided C exceeds a threshold value CT(Q); indeed, crucially we show that when Q is large, CT∝1/Q, meaning that oscillatory modes are preferred even when C itself is small. Similar behaviour is demonstrated in the case of fixed boundaries by means of a novel numerical solution. PMID:27956886

  19. Viscous driving of global oscillations in accretion discs around black holes

    NASA Astrophysics Data System (ADS)

    Miranda, Ryan; Horák, Jiří; Lai, Dong

    2015-01-01

    We examine the role played by viscosity in the excitation of global oscillation modes (both axisymmetric and non-axisymmetric) in accretion discs around black holes using two-dimensional hydrodynamic simulations. The turbulent viscosity is modelled by the α-ansatz, with different equations of state. We consider both discs with transonic radial inflows across the innermost stable circular orbit, and stationary discs truncated by a reflecting wall at their inner edge, representing a magnetosphere. In transonic discs, viscosity can excite several types of global oscillation modes. These modes are either axisymmetric with frequencies close to multiples of the maximum radial epicyclic frequency κmax, non-axisymmetric with frequencies close to multiples of the innermost stable orbit frequency ΩISCO, or hybrid modes whose frequencies are linear combinations of these two frequencies. Small values of the viscosity parameter α primarily produce non-axisymmetric modes, while axisymmetric modes become dominant for large α. The excitation of these modes may be related to an instability of the sonic point, at which the radial infall speed is equal to the sound speed of the gas. In discs with a reflective inner boundary, we explore the effect of viscosity on trapped p modes which are intrinsically overstable due to the corotation resonance effect. The effect of viscosity is either to reduce the growth rates of these modes, or to completely suppress them and excite a new class of higher frequency modes. The latter requires that the dynamic viscosity scales positively with the disc surface density, indicating that it is a result of the classic viscous overstability effect.

  20. Application of adjusted subpixel method (ASM) in HRCT measurements of the bronchi in bronchial asthma patients and healthy individuals.

    PubMed

    Mincewicz, Grzegorz; Rumiński, Jacek; Krzykowski, Grzegorz

    2012-02-01

    Recently, we described a model system which included corrections of high-resolution computed tomography (HRCT) bronchial measurements based on the adjusted subpixel method (ASM). To verify the clinical application of ASM by comparing bronchial measurements obtained by means of the traditional eye-driven method, subpixel method alone and ASM in a group comprised of bronchial asthma patients and healthy individuals. The study included 30 bronchial asthma patients and the control group comprised of 20 volunteers with no symptoms of asthma. The lowest internal and external diameters of the bronchial cross-sections (ID and ED) and their derivative parameters were determined in HRCT scans using: (1) traditional eye-driven method, (2) subpixel technique, and (3) ASM. In the case of the eye-driven method, lower ID values along with lower bronchial lumen area and its percentage ratio to total bronchial area were basic parameters that differed between asthma patients and healthy controls. In the case of the subpixel method and ASM, both groups were not significantly different in terms of ID. Significant differences were observed in values of ED and total bronchial area with both parameters being significantly higher in asthma patients. Compared to ASM, the eye-driven method overstated the values of ID and ED by about 30% and 10% respectively, while understating bronchial wall thickness by about 18%. Results obtained in this study suggest that the traditional eye-driven method of HRCT-based measurement of bronchial tree components probably overstates the degree of bronchial patency in asthma patients. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  1. Thermal convection in a magnetized conducting fluid with the Cattaneo-Christov heat-flow model

    NASA Astrophysics Data System (ADS)

    Bissell, J. J.

    2016-11-01

    By substituting the Cattaneo-Christov heat-flow model for the more usual parabolic Fourier law, we consider the impact of hyperbolic heat-flow effects on thermal convection in the classic problem of a magnetized conducting fluid layer heated from below. For stationary convection, the system is equivalent to that studied by Chandrasekhar (Hydrodynamic and Hydromagnetic Stability, 1961), and with free boundary conditions we recover the classical critical Rayleigh number Rc(c )(Q ) which exhibits inhibition of convection by the field according to Rc(c )→π2Q as Q →∞ , where Q is the Chandrasekhar number. However, for oscillatory convection we find that the critical Rayleigh number Rc(o )(Q ,P1,P2,C ) is given by a more complicated function of the thermal Prandtl number P1, magnetic Prandtl number P2 and Cattaneo number C. To elucidate features of this dependence, we neglect P2 (in which case overstability would be classically forbidden), and thereby obtain an expression for the Rayleigh number that is far less strongly inhibited by the field, with limiting behaviour Rc(o )→π √{Q }/ C , as Q →∞ . One consequence of this weaker dependence is that onset of instability occurs as overstability provided C exceeds a threshold value CT(Q); indeed, crucially we show that when Q is large, CT∝1 / √{Q }, meaning that oscillatory modes are preferred even when C itself is small. Similar behaviour is demonstrated in the case of fixed boundaries by means of a novel numerical solution.

  2. NASA Honors Legacy of Renowned Astrophysicist Stephen Hawking

    NASA Image and Video Library

    2018-03-14

    NASA is honoring visionary physicist Stephen Hawking, who died at his home in Cambridge, England, early Wednesday morning. Acting NASA Administrator Robert Lightfoot noted Hawking’s role as a “passionate communicator who wanted to share the excitement of discovery with all,” adding that his “impact cannot be overstated.” “Stephen’s breakthroughs in the fields of physics and astronomy not only changed how we view the cosmos, but also has played, and will continue to play, a pivotal role in shaping NASA’s efforts to explore our solar system and beyond,” said Lightfoot.

  3. Specifying design conservatism: Worst case versus probabilistic analysis

    NASA Technical Reports Server (NTRS)

    Miles, Ralph F., Jr.

    1993-01-01

    Design conservatism is the difference between specified and required performance, and is introduced when uncertainty is present. The classical approach of worst-case analysis for specifying design conservatism is presented, along with the modern approach of probabilistic analysis. The appropriate degree of design conservatism is a tradeoff between the required resources and the probability and consequences of a failure. A probabilistic analysis properly models this tradeoff, while a worst-case analysis reveals nothing about the probability of failure, and can significantly overstate the consequences of failure. Two aerospace examples will be presented that illustrate problems that can arise with a worst-case analysis.

  4. Reframing the risks and losses of teen mothering.

    PubMed

    SmithBattle, Lee

    2009-01-01

    Teen mothers often face a stigmatizing gaze based on the belief that early childbearing jeopardizes their life chances and the health and development of their children. Growing evidence suggests that the poor maternal-child outcomes associated with early childbearing have been overstated and may be explained by teen mothers' childhood disadvantage and adversities. After reviewing what is currently known about the relationships between early childbearing and maternal-child outcomes, as well as teen mothers' perspectives on mothering, clinical practices are suggested that address teen mothers' concerns, strengths, aspirations, and the long-term inequities that contribute to poor outcomes.

  5. On acquisition of programming knowledge

    NASA Technical Reports Server (NTRS)

    Amin, Ashok T.

    1987-01-01

    For the evolving discipline of programming, acquisition of programming knowledge is a difficult issue. Common knowledge results from the acceptance of proven techniques based on results of formal inquiries into the nature of the programming process. This is a rather slow process. In addition, the vast body of common knowledge needs to be explicated to a low enough level of details for it to be represented in the machine processable form. It is felt that this is an impediment to the progress of automatic programming. The importance of formal approaches cannot be overstated since their contributions lead to quantum leaps in the state of the art.

  6. 'PACE-Gate': When clinical trial evidence meets open data access.

    PubMed

    Geraghty, Keith J

    2017-08-01

    Science is not always plain sailing and sometimes the voyage is across an angry sea. A recent clinical trial of treatments for chronic fatigue syndrome (the PACE trial) has whipped up a storm of controversy. Patients claim the lead authors overstated the effectiveness of cognitive behavioural therapy and graded exercise therapy by lowering the thresholds they used to determine improvement. In this extraordinary case, patients discovered that the treatments tested had much lower efficacy after an information tribunal ordered the release of data from the PACE trial to a patient who had requested access using a freedom of information request.

  7. Research philosophy: towards an understanding.

    PubMed

    Crossan, Frank

    2003-01-01

    In this paper, Frank Crossan argues that the distinction between quantitative and qualitative philosophies and research methods is sometimes overstated, and that triangulation of methods in contemporary research is common. It is, therefore, important to understand the strengths and weaknesses of each approach, and this paper aims to provide the novice researcher with a basis for developing that understanding. A descriptive analysis of the philosophies of positivism and post-positivist thinking in relation to research methodology is presented both as an introduction to the philosophical basis of research, and as a sound basis from which to discuss the 'quantitative-qualitative' debate.

  8. The effects of studded tires on fatal crashes with passenger cars and the benefits of electronic stability control (ESC) in Swedish winter driving.

    PubMed

    Strandroth, Johan; Rizzi, Matteo; Olai, Maria; Lie, Anders; Tingvall, Claes

    2012-03-01

    This study set out to examine the effects of studded tires on fatal crashes on roads covered with ice or snow in Sweden and also to investigate the extra benefits of electronic stability control (ESC) during the winter months. Two different studies are presented in this paper. Both studies used an induced exposure approach. In the main study, 369 in-depth studies of fatal crashes with passenger cars were analyzed to determine whether loss-of-control (LOC) had been a major component or not. Only crashes involving cars without ESC and equipped with approved studded or non-studded winter tires were analyzed. The additional study used police-reported crashes that occurred during the winter seasons 2003-2010, involving passenger cars with and without ESC. While police records in Sweden do not include any tire information, it was assumed that most cars involved in crashes during the winter period would be equipped with studded tires. Findings in the main study showed that in 64% of the fatal crashes on roads covered with ice or snow LOC had been a major component. Furthermore, in 82% of LOC crashes, the passenger car over-steered prior to collision. Studded tires were found to have a statistically significant effect of 42% in terms of fatal crash reduction on roads covered with ice or snow, compared to non-studded winter tires. The effect on dry or wet roads in the winter was negative, although statistically non-significant. In the additional study, it was found that ESC further reduced crashes with injuries by 29%. The benefits on severe and fatal crashes were slightly greater (32%), although the lower 95% confidence limit was lower. Although studded tires were shown to reduce the risk of fatal crash involvement, compared to non-studded winter tires, the proportion of LOC and over-steering among cars with studded tires was large (59% and 49%, respectively). It was therefore concluded that studded tires do not prevent all LOC crashes, while ESC has benefits in those crashes since this technology mostly addresses over-steering. This is also supported by the fact that the share of LOC fatal crashes is considerably lower for ESC-equipped cars. This study recommends that non-ESC cars should be fitted with studded tires if they are to be driven on roads covered by ice or snow. If the proportion of studded tires is to be decreased on Swedish roads to reduce the about of hazardous particulates especially in built up areas, from a road safety point of view it is recommended that this should be done in phase with the implementation of ESC on all passenger cars. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Linked versus unlinked estimates of mortality and length of life by education and marital status: evidence from the first record linkage study in Lithuania.

    PubMed

    Shkolnikov, Vladimir M; Jasilionis, Domantas; Andreev, Evgeny M; Jdanov, Dmitri A; Stankuniene, Vladislava; Ambrozaitiene, Dalia

    2007-04-01

    Earlier studies have found large and increasing with time differences in mortality by education and marital status in post-Soviet countries. Their results are based on independent tabulations of population and deaths counts (unlinked data). The present study provides the first census-linked estimates of group-specific mortality and the first comparison between census-linked and unlinked mortality estimates for a post-Soviet country. The study is based on a data set linking 140,000 deaths occurring in 2001-2004 in Lithuania with the population census of 2001. The same socio-demographic information about the deceased is available from both the census and death records. Cross-tabulations and Poisson regressions are used to compare linked and unlinked data. Linked and unlinked estimates of life expectancies and mortality rate ratios are calculated with standard life table techniques and Poisson regressions. For the two socio-demographic variables under study, the values from the death records partly differ from those from the census records. The deviations are especially significant for education, with 72-73%, 66-67%, and 82-84% matching for higher education, secondary education, and lower education, respectively. For marital status, deviations are less frequent. For education and marital status, unlinked estimates tend to overstate mortality in disadvantaged groups and they understate mortality in advantaged groups. The differences in inter-group life expectancy and the mortality rate ratios thus are significantly overestimated in the unlinked data. Socio-demographic differences in mortality previously observed in Lithuania and possibly other post-Soviet countries are overestimated. The growth in inequalities over the 1990s is real but might be overstated. The results of this study confirm the existence of large and widening health inequalities but call for better data.

  10. The impact of retirement on health: quasi-experimental methods using administrative data.

    PubMed

    Horner, Elizabeth Mokyr; Cullen, Mark R

    2016-02-19

    Is retirement good or bad for health? Disentangling causality is difficult. Much of the previous quasi-experimental research on the effect of health on retirement used self-reported health and relied upon discontinuities in public retirement incentives across Europe. The current study investigated the effect of retirement on health by exploiting discontinuities in private retirement incentives to test the effect of retirement on health using a quasi-experimental study design. Secondary data (1997-2009) on a cohort of male manufacturing workers in a United States setting. Health status was determined using claims data from private insurance and Medicare. Analyses used employer-based administrative and claims data and claim data from Medicare. Widely used selection on observables models overstate the negative impact of retirement due to the endogeneity of the decision to retire. In addition, health status as measured by administrative claims data provide some advantages over the more commonly used survey items. Using an instrument and administrative health records, we find null to positive effects from retirement on all fronts, with a possible exception of increased risk for diabetes. This study provides evidence that retirement is not detrimental and may be beneficial to health for a sample of manufacturing workers. In addition, it supports previous research indicating that quasi-experimental methodologies are necessary to evaluate the relationship between retirement and health, as any selection on observable model will overstate the negative relationship of retirement on health. Further, it provides a model for how such research could be implemented in countries like the United States that do not have a strong public pension program. Finally, it demonstrates that such research need-not rely upon survey data, which has certain shortcomings and is not always available for homogenous samples.

  11. Debating Organ Procurement Policy Without Illusions.

    PubMed

    Hippen, Benjamin

    2015-10-01

    In this perspective, I review and critique claims that the transplant waiting list overstates the demand for kidneys and correct a few mischaracterizations of some structural barriers to increasing rates of transplantation. The solutions to the shortage of organs proffered by opponents of financial incentives fail to account for a panoply of clinical, regulatory, and financial realities of transplantation centers in the United States in ways that undermine the thesis that a trial of financial incentives for organ procurement is not warranted at this time. I conclude with some personal pessimistic reflections on the progress of this debate. Copyright © 2015 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  12. Effect of extended tooth contact on the modeling of spur gear transmissions

    NASA Technical Reports Server (NTRS)

    Oswald, Fred B.; Coy, John J.; Lin, Hsiang Hsi; Wang, Jifeng

    1993-01-01

    In some gear dynamic models, the effect of tooth flexibility is ignored when the model determines which pairs of teeth are in contact. Deflection of loaded teeth is not introduced until the equations of motion are solved. This means the zone of tooth contact and average tooth meshing stiffness are underestimated and the individual tooth load is overstated, especially for heavily-loaded gears. The static transmission error and dynamic load of heavily-loaded, low-contact-ratio spur gears is compared with this effect both neglected and included. Neglecting the effect yields an underestimate of resonance speeds and an overestimate of the dynamic load.

  13. Lower extremity manifestations of "skin-popping" an illicit drug use technique: A report of two cases.

    PubMed

    Canales, Michael; Gerhard, John; Younce, Erin

    2015-06-01

    Presented is a rare case of tibial and fibular osteomyelitis and a case of fibular periositis, both a direct consequence of a peculiar drug use technique. The osseous manifestations secondary to presentation of necrotic wounds with indurated rim and serous drainage with associated cellulitis, both resulting from "skin popping." Due to the complex treatment plan required, the importance of a motivated patient, a strong social support system, a controlled environment, and a multidisciplinary team cannot be overstated. Despite comprehensive efforts, devastating consequences may be unavoidable as individuals plunge downward, victimized by their addiction. 4. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Bias, misleading information and lack of respect for alternative views have distorted perceptions of myalgic encephalomyelitis/chronic fatigue syndrome and its treatment.

    PubMed

    Goudsmit, Ellen; Howes, Sandra

    2017-08-01

    The PACE trial is one of the most recent studies evaluating cognitive behavioural therapy and graded exercise therapy for myalgic encephalomyelitis/chronic fatigue syndrome. These interventions are based on a model which assumes that symptoms are perpetuated by factors such as misguided beliefs and a lack of activity. Our analysis indicates that the researchers have shown significant bias in their accounts of the literature and may also have overstated the effectiveness of the above treatments. We submit that their approach to criticisms undermines the scientific process and is inconsistent with best practice.

  15. Low Self-Control Among South Korean Adolescents: A Test of Gottfredson and Hirschi's Generality Hypothesis.

    PubMed

    Yun, Ilhong; Kim, Seung-Gon; Kwon, Sangro

    2016-08-01

    Theoretical propositions and empirical tests of Gottfredson and Hirschi's general theory continue to permeate the criminological literature. Nevertheless, the vast majority of studies have been conducted in North America and some European countries. Only a handful of empirical works have been conducted in East Asia. To further test the generality assertion of Gottfredson and Hirschi, the current study examines low self-control's efficacy in predicting the involvement of South Korean adolescents in typical delinquency, drinking, smoking, Internet addiction, and smartphone addiction. The presented findings largely support the generality hypothesis, although the theorists' assertion seems to be somewhat overstated. © The Author(s) 2015.

  16. Beyond singular values and loop shapes

    NASA Technical Reports Server (NTRS)

    Stein, G.

    1985-01-01

    The status of singular value loop-shaping as a design paradigm for multivariable feedback systems is reviewed. It shows that this paradigm is an effective design tool whenever the problem specifications are spacially round. The tool can be arbitrarily conservative, however, when they are not. This happens because singular value conditions for robust performance are not tight (necessary and sufficient) and can severely overstate actual requirements. An alternate paradign is discussed which overcomes these limitations. The alternative includes a more general problem formulation, a new matrix function mu, and tight conditions for both robust stability and robust performance. The state of the art currently permits analysis of feedback systems within this new paradigm. Synthesis remains a subject of research.

  17. The Onset of Double Diffusive Convection in a Viscoelastic Fluid-Saturated Porous Layer with Non-Equilibrium Model

    PubMed Central

    Yang, Zhixin; Wang, Shaowei; Zhao, Moli; Li, Shucai; Zhang, Qiangyong

    2013-01-01

    The onset of double diffusive convection in a viscoelastic fluid-saturated porous layer is studied when the fluid and solid phase are not in local thermal equilibrium. The modified Darcy model is used for the momentum equation and a two-field model is used for energy equation each representing the fluid and solid phases separately. The effect of thermal non-equilibrium on the onset of double diffusive convection is discussed. The critical Rayleigh number and the corresponding wave number for the exchange of stability and over-stability are obtained, and the onset criterion for stationary and oscillatory convection is derived analytically and discussed numerically. PMID:24312193

  18. The onset of double diffusive convection in a viscoelastic fluid-saturated porous layer with non-equilibrium model.

    PubMed

    Yang, Zhixin; Wang, Shaowei; Zhao, Moli; Li, Shucai; Zhang, Qiangyong

    2013-01-01

    The onset of double diffusive convection in a viscoelastic fluid-saturated porous layer is studied when the fluid and solid phase are not in local thermal equilibrium. The modified Darcy model is used for the momentum equation and a two-field model is used for energy equation each representing the fluid and solid phases separately. The effect of thermal non-equilibrium on the onset of double diffusive convection is discussed. The critical Rayleigh number and the corresponding wave number for the exchange of stability and over-stability are obtained, and the onset criterion for stationary and oscillatory convection is derived analytically and discussed numerically.

  19. Overestimation of marsh vulnerability to sea level rise

    USGS Publications Warehouse

    Kirwan, Matthew L.; Temmerman, Stijn; Skeehan, Emily E.; Guntenspergen, Glenn R.; Fagherazzi, Sergio

    2016-01-01

    Coastal marshes are considered to be among the most valuable and vulnerable ecosystems on Earth, where the imminent loss of ecosystem services is a feared consequence of sea level rise. However, we show with a meta-analysis that global measurements of marsh elevation change indicate that marshes are generally building at rates similar to or exceeding historical sea level rise, and that process-based models predict survival under a wide range of future sea level scenarios. We argue that marsh vulnerability tends to be overstated because assessment methods often fail to consider biophysical feedback processes known to accelerate soil building with sea level rise, and the potential for marshes to migrate inland.

  20. The ethics of forensic practice: reclaiming the wasteland.

    PubMed

    Morse, Stephen J

    2008-01-01

    After beginning with a warm appreciation of Alan Stone's scholarship and character, this article argues that Stone's woeful characterization of forensic practice as a wasteland that has no genuine ethical guide to practice and little to contribute is vastly overstated. It claims that the basis for useful ethical practice is rooted in a proper understanding of the law's folk psychological model of behavior and criteria. Then it suggests the proper bounds of forensic practice, including an aspirational list of do's and don'ts. The view presented is deflationary and cautious compared to what the law permits and most practitioners do, but it still leaves forensic practitioners with a wide and important role in the legal system.

  1. The tightrope between drawing media attention and exaggeration

    NASA Astrophysics Data System (ADS)

    Savenije, Hubert H. G.

    2017-04-01

    To draw media attention, it is not sufficient to present your research in a simple and understandable way. The message should also be news-worthy, controversial or surprising. Unfortunately well-balanced, well-founded and considerate statements are seldom attractive to the media. The media want something that creates commotion. This may tempt one to overstate the impact of research results, or to exaggerate its relevance. But this is dangerous, because if you do manage to draw the attention of the media, then the headline maker will surely make your claim bolder then you intended it to be. I had to learn this the hard way. I'll illustrate this with a few examples from my own media experience.

  2. U-Th-Pb, Sm-Nd, Rb-Sr, and Lu-Hf systematics of returned Mars samples

    NASA Technical Reports Server (NTRS)

    Tatsumoto, M.; Premo, W. R.

    1988-01-01

    The advantage of studying returned planetary samples cannot be overstated. A wider range of analytical techniques with higher sensitivities and accuracies can be applied to returned samples. Measurement of U-Th-Pb, Sm-Nd, Rb-Sr, and Lu-Hf isotopic systematics for chronology and isotopic tracer studies of planetary specimens cannot be done in situ with desirable precision. Returned Mars samples will be examined using all the physical, chemical, and geologic methods necessary to gain information on the origin and evolution of Mars. A returned Martian sample would provide ample information regarding the accretionary and evolutionary history of the Martian planetary body and possibly other planets of our solar system.

  3. Cultural transmission of civic attitudes.

    PubMed

    Miles-Touya, Daniel; Rossi, Máximo

    2016-01-01

    In this empirical paper we attempt to measure the separate influence on civic engagement of educational attainment and cultural transmission of civic attitudes. Unlike most of the previous empirical works on this issue, we are able to approximate the cultural transmission of civic attitudes. We observe that civic returns to education are overstated when the transmission of civic attitudes is ignored. Moreover, the transmission of civic attitudes significantly enhances civic involvement and reinforces civic returns to education. Our findings are in line with the proposals of civic virtue theorists or grass movements who suggest that citizenship education should be included in the compulsory school curricula since, if not, families or local communities will only transmit their particular view of the world.

  4. Water quality key to protecting patients.

    PubMed

    Pearson, Susan

    2012-11-01

    According to David Graham of the Scottish National Blood Transfusion Service (SNBTS), "the importance of the safe diagnosis and treatment of patients cannot be overstated - yet the role played by water quality in patient safety has sometimes been under-stated". David Graham was speaking at a one day Pall Medical-sponsored meeting on the prevention and control of healthcare-associated waterborne infections in healthcare facilities held in Edinburgh earlier this year. David Graham, other speakers, and the chair, Consultant Microbiologist and Infection Prevention and Control Doctor for NHS Grampian, Dr Anne Marie Karcher, stressed that good quality water is essential in healthcare premises to prevent the potentially catastrophic consequences of contaminated water for some patients. Susan Pearson BSc reports.

  5. Diagnosis and management of hemangiomas and vascular malformations of the head and neck.

    PubMed

    Buckmiller, L M; Richter, G T; Suen, J Y

    2010-07-01

    Vascular anomalies are congenital errors in vascular development. They frequently involve the head, neck, and oral cavity. Subdivided into vascular tumors (hemangiomas) and vascular malformations, vascular anomalies remain poorly understood. However, growing interest and recent advances in the diagnosis, management, and molecular characterization of these lesions are improving treatment strategies. The role of the multidisciplinary team cannot be overstated. This review provides both basic and up-to-date knowledge on the most common vascular anomalies encountered by physicians and practitioners. Because treatment options for vascular anomalies are widely variable and often debated, this report aims to provide a comprehensive approach to these lesions based upon current concepts and practical clinical experience.

  6. NATURE VERSUS NURTURE: DEATH OF A DOGMA, AND THE ROAD AHEAD

    PubMed Central

    Traynor, Bryan J.; Singleton, Andrew B.

    2010-01-01

    Interaction between the genome and the environment has been widely discussed in the literature, but has the importance ascribed to understanding these interactions been overstated? In this opinion piece, we critically discuss gene-environment interactions and attempt to answer three key questions: First, is it likely that gene-environment interactions actually exist? Second, what is the realistic value of trying to unravel these interactions, both in terms of understanding disease pathogenesis and as a means of ameliorating disease? Finally, and most importantly, do the technologies and methodologies exist to facilitate an unbiased search for gene-environment interactions? Addressing these questions highlights key areas of feasibility that must be considered in this area of research. PMID:20955927

  7. Incorporating Anthropogenic Influences into Fire Probability Models: Effects of Human Activity and Climate Change on Fire Activity in California.

    PubMed

    Mann, Michael L; Batllori, Enric; Moritz, Max A; Waller, Eric K; Berck, Peter; Flint, Alan L; Flint, Lorraine E; Dolfi, Emmalee

    2016-01-01

    The costly interactions between humans and wildfires throughout California demonstrate the need to understand the relationships between them, especially in the face of a changing climate and expanding human communities. Although a number of statistical and process-based wildfire models exist for California, there is enormous uncertainty about the location and number of future fires, with previously published estimates of increases ranging from nine to fifty-three percent by the end of the century. Our goal is to assess the role of climate and anthropogenic influences on the state's fire regimes from 1975 to 2050. We develop an empirical model that integrates estimates of biophysical indicators relevant to plant communities and anthropogenic influences at each forecast time step. Historically, we find that anthropogenic influences account for up to fifty percent of explanatory power in the model. We also find that the total area burned is likely to increase, with burned area expected to increase by 2.2 and 5.0 percent by 2050 under climatic bookends (PCM and GFDL climate models, respectively). Our two climate models show considerable agreement, but due to potential shifts in rainfall patterns, substantial uncertainty remains for the semiarid inland deserts and coastal areas of the south. Given the strength of human-related variables in some regions, however, it is clear that comprehensive projections of future fire activity should include both anthropogenic and biophysical influences. Previous findings of substantially increased numbers of fires and burned area for California may be tied to omitted variable bias from the exclusion of human influences. The omission of anthropogenic variables in our model would overstate the importance of climatic ones by at least 24%. As such, the failure to include anthropogenic effects in many models likely overstates the response of wildfire to climatic change.

  8. Incorporating Anthropogenic Influences into Fire Probability Models: Effects of Human Activity and Climate Change on Fire Activity in California

    PubMed Central

    Batllori, Enric; Moritz, Max A.; Waller, Eric K.; Berck, Peter; Flint, Alan L.; Flint, Lorraine E.; Dolfi, Emmalee

    2016-01-01

    The costly interactions between humans and wildfires throughout California demonstrate the need to understand the relationships between them, especially in the face of a changing climate and expanding human communities. Although a number of statistical and process-based wildfire models exist for California, there is enormous uncertainty about the location and number of future fires, with previously published estimates of increases ranging from nine to fifty-three percent by the end of the century. Our goal is to assess the role of climate and anthropogenic influences on the state’s fire regimes from 1975 to 2050. We develop an empirical model that integrates estimates of biophysical indicators relevant to plant communities and anthropogenic influences at each forecast time step. Historically, we find that anthropogenic influences account for up to fifty percent of explanatory power in the model. We also find that the total area burned is likely to increase, with burned area expected to increase by 2.2 and 5.0 percent by 2050 under climatic bookends (PCM and GFDL climate models, respectively). Our two climate models show considerable agreement, but due to potential shifts in rainfall patterns, substantial uncertainty remains for the semiarid inland deserts and coastal areas of the south. Given the strength of human-related variables in some regions, however, it is clear that comprehensive projections of future fire activity should include both anthropogenic and biophysical influences. Previous findings of substantially increased numbers of fires and burned area for California may be tied to omitted variable bias from the exclusion of human influences. The omission of anthropogenic variables in our model would overstate the importance of climatic ones by at least 24%. As such, the failure to include anthropogenic effects in many models likely overstates the response of wildfire to climatic change. PMID:27124597

  9. The Dynamics of Dense Planetary Rings.

    NASA Astrophysics Data System (ADS)

    Mosqueira, Ignacio

    1995-01-01

    We study the dynamics of a two-mode narrow ring in the case that one of the modes dominates the overall ring perturbation. We use a simple two-streamline self -gravity model, including viscosity, and shepherd satellites. As might be expected, we find that n m = 1 mode appears to be a natural end state for the rings, inasmuch as the presence of a dominant eccentric mode inhibits the growth of other modes, but the reverse is not true. Why some rings exhibit other m values only remains unexplained. Using a modified N-body code to include periodic boundary conditions in a perturbed shear flow, we investigate the role of viscosity on the dynamics of perturbed rings with optical depth tau ~ 1. In particular, we are concerned with rings such that qe = a{de over da} ne 0, where a is the semi-major axis and e is the eccentricity. We confirm the possibility that, for a sufficiently perturbed ring, the angular momentum luminosity may reverse direction with respect to the unperturbed ring (Borderies et al. 1983a). We use observationally constrained parameters for the delta and epsilon Uranian rings, as well as the outer portion of Saturn's B ring. We find that understanding the effects of viscosity for the Uranian rings requires that both local and non-local transport terms be considered if the coefficient of restitution experimentally obtained by Bridges et al. (1984) is appropriate for ring particles. We also find evidence that the criterion for viscous overstability is satisfied in the case of high optical depth rings, as originally proposed by Borderies et al. (1985), making viscous overstability a leading candidate mechanism to explain the non-axisymmetric structure present in the outer portion of Saturn's B ring. To better understand our path-code results we extend a non-local and incompressible fluid model used by Borderies et al. (1985) for dense rings. We incorporate local and non-local transport terms as well as compressibility, while retaining the same number of arbitrary model parameters.

  10. Theories of dynamical phenomena in sunspots

    NASA Technical Reports Server (NTRS)

    Thomas, J. H.

    1981-01-01

    Attempts that have been made to understand and explain observed dynamical phenomena in sunspots within the framework of magnetohydrodynamic theory are surveyed. The qualitative aspects of the theory and physical arguments are emphasized, with mathematical details generally avoided. The dynamical phenomena in sunspots are divided into two categories: aperiodic (quasi-steady) and oscillatory. For each phenomenon discussed, the salient observational features that any theory should explain are summarized. The two contending theoretical models that can account for the fine structure of the Evershed motion, namely the convective roll model and the siphon flow model, are described. With regard to oscillatory phenomena, attention is given to overstability and oscillatory convection, umbral oscillations and flashes. penumbral waves, five-minute oscillations in sunspots, and the wave cooling of sunspots.

  11. Google Earth as a method for connecting scientific research with the World

    NASA Astrophysics Data System (ADS)

    Graham, J. R.

    2012-12-01

    Google Earth has proven itself to be an exceptionally successful and ambitious application: fully capable as a scientific tool, yet able to also satisfy the intellectual and virtual touristic needs of students, educators and the general public. It is difficult to overstate Google Earth's impact on our understanding of the World we inhabit, and yet there is also considerable potential that remains unexplored. This paper will discuss Google Earth's potential as a social network for the science community - connecting the general public with scientists, and scientists with their research. This paper will look at the University of Lethbridge's RAVE (Reaching Audiences through Virtual Entryways) project as a model for how this social network can function within the Google Earth environment.

  12. The missing discourse of development: commentary on Lerum and Dworkin.

    PubMed

    Else-Quest, Nicole M; Hyde, Janet Shibley

    2009-01-01

    Lerum and Dworkin offer a provocative interdisciplinary feminist commentary on the Report of the APA (American Psychological Association) Task Force on the Sexualization of Girls. This commentary notes limitations to their argument and evidence, which make it a less convincing critique of the report's conclusions. Most notably, Lerum and Dworkin omit a developmental approach to the topic of sexualization and media exposure. In addition, their criticism that the report over-determines the negative effects (i.e., overstates the negative effects and ignores the positive effects) of sexualization on girls is unsupported by the empirical literature. This commentary also addresses their concerns about the language used in the report and highlights the need for clear and precise language in this dialogue.

  13. Enhancement and character recognition of the erased colophon of a 15th-century Hebrew prayer book

    NASA Astrophysics Data System (ADS)

    Walvoord, Derek J.; Easton, Roger L., Jr.; Knox, Keith T.; Heimbueger, Matthew

    2005-01-01

    A handwritten codex often included an inscription that listed facts about its publication, such as the names of the scribe and patron, date of publication, the city where the book was copied, etc. These facts obviously provide essential information to a historian studying the provenance of the codex. Unfortunately, this page was sometimes erased after the sale of the book to a new owner, often by scraping off the original ink. The importance of recovering this information would be difficult to overstate. This paper reports on the methods of imaging, image enhancement, and character recognition that were applied to this page in a Hebrew prayer book copied in Florence in the 15th century.

  14. Enhancement and character recognition of the erased colophon of a 15th-century Hebrew prayer book

    NASA Astrophysics Data System (ADS)

    Walvoord, Derek J.; Easton, Roger L., Jr.; Knox, Keith T.; Heimbueger, Matthew

    2004-12-01

    A handwritten codex often included an inscription that listed facts about its publication, such as the names of the scribe and patron, date of publication, the city where the book was copied, etc. These facts obviously provide essential information to a historian studying the provenance of the codex. Unfortunately, this page was sometimes erased after the sale of the book to a new owner, often by scraping off the original ink. The importance of recovering this information would be difficult to overstate. This paper reports on the methods of imaging, image enhancement, and character recognition that were applied to this page in a Hebrew prayer book copied in Florence in the 15th century.

  15. Update on narrow band imaging in disorders of the upper gastrointestinal tract.

    PubMed

    Singh, Rajvinder; Lee, Shok Y; Vijay, Nimal; Sharma, Prateek; Uedo, Noriya

    2014-03-01

    With the ever-increasing concern regarding morbidity and mortality associated with diseases of the gastrointestinal tract, the importance of an effective and efficient diagnostic tool cannot be overstated. The standard of care currently is an examination using conventional white light endoscopy. This approach may occasionally overlook areas exhibiting a premalignant change. Numerous image-enhanced modalities have been recently introduced. Narrow band imaging (NBI) appears to be the most prominent of these and perhaps the most commonly used. Thepresent review will focus on some of the newer studies on NBI and its utility in the diagnosis of malignant, pre-malignant and chronic inflammatory conditions of the upper gastrointestinal tract. © 2013 The Authors. Digestive Endoscopy © 2013 Japan Gastroenterological Endoscopy Society.

  16. Nature's style: Naturally trendy

    USGS Publications Warehouse

    Cohn, T.A.; Lins, H.F.

    2005-01-01

    Hydroclimatological time series often exhibit trends. While trend magnitude can be determined with little ambiguity, the corresponding statistical significance, sometimes cited to bolster scientific and political argument, is less certain because significance depends critically on the null hypothesis which in turn reflects subjective notions about what one expects to see. We consider statistical trend tests of hydroclimatological data in the presence of long-term persistence (LTP). Monte Carlo experiments employing FARIMA models indicate that trend tests which fail to consider LTP greatly overstate the statistical significance of observed trends when LTP is present. A new test is presented that avoids this problem. From a practical standpoint, however, it may be preferable to acknowledge that the concept of statistical significance is meaningless when discussing poorly understood systems.

  17. Nature's style: Naturally trendy

    NASA Astrophysics Data System (ADS)

    Cohn, Timothy A.; Lins, Harry F.

    2005-12-01

    Hydroclimatological time series often exhibit trends. While trend magnitude can be determined with little ambiguity, the corresponding statistical significance, sometimes cited to bolster scientific and political argument, is less certain because significance depends critically on the null hypothesis which in turn reflects subjective notions about what one expects to see. We consider statistical trend tests of hydroclimatological data in the presence of long-term persistence (LTP). Monte Carlo experiments employing FARIMA models indicate that trend tests which fail to consider LTP greatly overstate the statistical significance of observed trends when LTP is present. A new test is presented that avoids this problem. From a practical standpoint, however, it may be preferable to acknowledge that the concept of statistical significance is meaningless when discussing poorly understood systems.

  18. Nature versus nurture: death of a dogma, and the road ahead.

    PubMed

    Traynor, Bryan J; Singleton, Andrew B

    2010-10-21

    Interaction between the genome and the environment has been widely discussed in the literature, but has the importance ascribed to understanding these interactions been overstated? In this opinion piece, we critically discuss gene-environment interactions and attempt to answer three key questions. First, is it likely that gene-environment interactions actually exist? Second, what is the realistic value of trying to unravel these interactions, both in terms of understanding disease pathogenesis and as a means of ameliorating disease? Finally, and most importantly, do the technologies and methodologies exist to facilitate an unbiased search for gene-environment interactions? Addressing these questions highlights key areas of feasibility that must be considered in this area of research. Copyright © 2010 Elsevier Inc. All rights reserved.

  19. Pathology data integration with eXtensible Markup Language.

    PubMed

    Berman, Jules J

    2005-02-01

    It is impossible to overstate the importance of XML (eXtensible Markup Language) as a data organization tool. With XML, pathologists can annotate all of their data (clinical and anatomic) in a format that can transform every pathology report into a database, without compromising narrative structure. The purpose of this manuscript is to provide an overview of XML for pathologists. Examples will demonstrate how pathologists can use XML to annotate individual data elements and to structure reports in a common format that can be merged with other XML files or queried using standard XML tools. This manuscript gives pathologists a glimpse into how XML allows pathology data to be linked to other types of biomedical data and reduces our dependence on centralized proprietary databases.

  20. [The expressions of anxiety in the elderly. Their diagnosis and therapy].

    PubMed

    Scapicchio, P L

    1995-10-01

    Among the most common manifestations of anxiety in the elderly are those associated with neurological disorders. The etiology is often unclear, as anxiety and agitation may be a consequence of insight into the cognitive impairment rather than the direct expression of the neurological deficit. Benzodiazepines are the treatment of choice, particularly the 3-OH compounds that are non oxidised and without active metabolites. Concern about the use of benzodiazepines in the elderly may have been overstated. If used judiciously this class of drugs can prove extremely helpful in reducing day-time anxiety and night-time insomnia. Other medications that are commonly used to treat agitation and disruptive behaviour in demented elderly patients include antipsychotics, beta-blockers, trazodone, buspirone, anticonvulsants.

  1. Genomic research, publics and experts in Latin America: Nation, race and body

    PubMed Central

    Wade, Peter; López-Beltrán, Carlos; Restrepo, Eduardo; Santos, Ricardo Ventura

    2015-01-01

    The articles in this issue highlight contributions that studies of Latin America can make to wider debates about the effects of genomic science on public ideas about race and nation. We argue that current ideas about the power of genomics to transfigure and transform existing ways of thinking about human diversity are often overstated. If a range of social contexts are examined, the effects are uneven. Our data show that genomic knowledge can unsettle and reinforce ideas of nation and race; it can be both banal and highly politicized. In this introduction, we outline concepts of genetic knowledge in society; theories of genetics, nation and race; approaches to public understandings of science; and the Latin American contexts of transnational ideas of nation and race. PMID:27479996

  2. Birth weight and cognitive development in adolescence: causal relationship or social selection?

    PubMed

    Gorman, Bridget K

    2002-01-01

    Using data from the National Longitudinal Survey of Adolescent Health (Add Health), I investigate the relationship between birth weight and cognitive development among adolescents aged 12-17. Initial OLS regression models reveal a significant, positive relationship between low birth weight and verbal ability. Controlling for demographic, socioeconomic, and other adolescent characteristics modifies, but does not eliminate, this relationship. Additional models that stratify the sample by parental education illustrate the greater importance of other family and adolescent characteristics for cognitive development in adolescence, and a diminished role of birth weight. In the final section of the paper, fixed effects models of non-twin full siblings indicate no significant association between birth weight and verbal ability, suggesting that traditional cross-sectional models overstate the influence of birth weight for cognitive development in adolescence.

  3. Performance of magnetic field‐guided navigation system for interventional neurosurgical and cardiac procedures

    PubMed Central

    Chu, James C.H.; Hsi, Wen Chien; Hubbard, Lincoln; Zhang, Yunkai; Bernard, Damian; Reeder, Pamela; Lopes, Demetrius

    2005-01-01

    A hospital‐based magnetic guidance system (MGS) was installed to assist a physician in navigating catheters and guide wires during interventional cardiac and neurosurgical procedures. The objective of this study is to examine the performance of this magnetic field‐guided navigation system. Our results show that the system's radiological imaging components produce images with quality similar to that produced by other modern fluoroscopic devices. The system's magnetic navigation components also deflect the wire and catheter tips toward the intended direction. The physician, however, will have to oversteer the wire or catheter when defining the steering angle during the procedure. The MGS could be clinically useful in device navigation deflection and vessel access. PACS numbers: 07.55.Db, 07.85.‐m PMID:16143799

  4. The spirit of hypnosis: doing hypnosis versus being hypnotic.

    PubMed

    Yapko, Michael D

    2014-01-01

    The spirit of hypnosis is reflected in the belief that people are more resourceful than they realize and through hypnosis can create meaningful possibilities. Thus, it is puzzling why hypnosis isn't better regarded. Do we present as too internally conflicted to inspire others' confidence? Do we overstate the dangers of hypnosis and scare people away? Do we define hypnosis as such a unique approach that others don't see its relevance for their work? Self-exploration is important if we want to ensure we are not unwittingly adding to our image problems as a field. Beyond these considerations, the novel and spirited application of hypnosis in the context of captive elephant breeding is discussed, as is a personal acknowledgment of some of the pioneers who manifested the spirit of hypnosis.

  5. Mode-Stirred Method Implementation for HIRF Susceptibility Testing and Results Comparison with Anechoic Method

    NASA Technical Reports Server (NTRS)

    Nguyen, Truong X.; Ely, Jay J.; Koppen, Sandra V.

    2001-01-01

    This paper describes the implementation of mode-stirred method for susceptibility testing according to the current DO-160D standard. Test results on an Engine Data Processor using the implemented procedure and the comparisons with the standard anechoic test results are presented. The comparison experimentally shows that the susceptibility thresholds found in mode-stirred method are consistently higher than anechoic. This is consistent with the recent statistical analysis finding by NIST that the current calibration procedure overstates field strength by a fixed amount. Once the test results are adjusted for this value, the comparisons with the anechoic results are excellent. The results also show that test method has excellent chamber to chamber repeatability. Several areas for improvements to the current procedure are also identified and implemented.

  6. Anosmia: Differential diagnosis, evaluation, and management.

    PubMed

    Scangas, George A; Bleier, Benjamin S

    2017-01-01

    The ability to scrutinize our surroundings remains heavily dependent on the sense of smell. From the ability to detect dangerous situations such as fires to the recollection of a fond memory triggered by an odor, the advantages of an intact olfactory system cannot be overstated. Outcomes studies have highlighted the profound negative impact of anosmia and parosmia on the overall quality of life. The National Institute on Deafness and Other Communication Disorders estimates that ∼1.4% of the United States population experiences chronic olfactory dysfunction and smell loss. Efforts have focused on improving both the diagnosis of olfactory dysfunction through olfactory testing and improved reporting of treatment outcomes of olfactory training. The purpose of this article was to review the differential diagnosis, workup, and current treatment strategies of anosmia and smell disorders.

  7. Comment on the implications of external price referencing of pharmaceuticals in Middle East countries.

    PubMed

    Carapinha, João L

    2016-01-01

    External Price Referencing (EPR) is frequently used by countries to control pharmaceutical prices but studies to substantiate its use in the Middle East (ME) is lacking. The paper by Kalo et al set-out to fill this lacuna through three objectives: i) to document the use of EPR in 7 ME countries, ii) to assess whether pharmaceutical EPR resulted in a narrow price corridor for patented pharmaceuticals, and iii) to analyse factors influencing pharmaceutical prices. This comment discusses why the paper fell short of achieving these objectives and over-stated the results. Despite a thought-provoking contribution, objective 1 presented few new insights on EPR mechanisms, objective 2 deployed an inappropriate research design, and the policy implications of objective 3 are voided given the choice of explanatory variables.

  8. Employment Impact of Sugar-Sweetened Beverage Taxes

    PubMed Central

    Powell, Lisa M.; Wada, Roy; Persky, Joseph J.; Chaloupka, Frank J.

    2014-01-01

    Objectives. We assessed the impact of sugar-sweetened beverage (SSB) taxes on net employment. Methods. We used a macroeconomic simulation model to assess the employment impact of a 20% SSB tax accounting for changes in SSB demand, substitution to non-SSBs, income effects, and government expenditures of tax revenues for Illinois and California in 2012. Results. We found increased employment of 4406 jobs in Illinois and 6654 jobs in California, representing a respective 0.06% and 0.03% change in employment. Declines in employment within the beverage industry occurred but were offset by new employment in nonbeverage industry and government sectors. Conclusions. SSB taxes do not have a negative impact on state-level employment, and industry claims of regional job losses are overstated and may mislead lawmakers and constituents. PMID:24524492

  9. Mineral resource of the month: manganese

    USGS Publications Warehouse

    Corathers, Lisa A.

    2012-01-01

    Manganese is a silver-colored metal resembling iron and often found in conjunction with iron. The earliest-known human use of manganese compounds was in the Stone Age, when early humans used manganese dioxide as pigments in cave paintings. In ancient Rome and Egypt, people started using it to color or remove the color from glass - a practice that continued to modern times. Today, manganese is predominantly used in metallurgical applications as an alloying addition, particularly in steel and cast iron production. Steel and cast iron together provide the largest market for manganese (historically 85 to 90 percent), but it is also alloyed with nonferrous metals such as aluminum and copper. Its importance to steel cannot be overstated, as almost all types of steel contain manganese and could not exist without it.

  10. Additional Evidence is Needed to Recommend Acquiring a Dog to Families of Children with Autism Spectrum Disorder: A Response to Wright and Colleagues.

    PubMed

    Crossman, Molly K; Kazdin, Alan E

    2016-01-01

    Caregivers of children with autism spectrum disorder are vulnerable to overstated benefits of interventions, and such overstatements are common with interventions involving animals. This response to Wright, Hall, Hames, Hardmin, Mills, the Paws Team, and Mills' (2015) article, "Acquiring a Pet Dog Significantly Reduces Stress of Primary Careers for Children with Autism Spectrum Disorder: A Prospective Case Control Study," details why that study's conclusions are premature. Specific limitations of the study are detailed, including overstatements of the supportive literature, problems with the design, and mismatch between the findings and conclusions. The purpose is not to challenge the benefits of pet ownership, but to point out that those benefits have not yet been established.

  11. Management of occult stress urinary incontinence with prolapse surgery.

    PubMed

    Al-Mandeel, H; Al-Badr, A

    2013-08-01

    Pelvic organ prolapse (POP) and stress urinary incontinence (SUI), are two common health-related conditions, each affecting up to 50% women worldwide. Stress urinary incontinence only observed after the reduction of co-existent prolapse is called occult SUI (OSUI), and is found in up to 80% of women with advanced POP. Although there is no consensus on how to diagnose OSUI, there are several reported methods to better diagnose. Counseling symptomatically continent women with POP concerning the potential risk for developing SUI postoperatively cannot be overstated. Evidence suggests that positive OSUI in symptomatically continent women who are planning to have POP repair is associated with a high risk of POSUI, furthermore, adding continence procedure is found to reduce postoperative SUI. Therefore, adding continence surgery at the time of POP surgery in patients who are found to have OSUI preoperatively is advocated.

  12. Requirements for munitions lift trailers to support strategic bombers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1985-05-21

    Munitions lift trailers are large support vehicles used to transport and load air launched cruise missiles and other nuclear weapons onto strategic bombers. The Air Force has identified total requirements for 245 trailers for B-52 and B-1B bombers. About one-third of these trailers have been acquired. The Air Force Aeronautical Systems Command is considering remanufacturing 80 of the lift trailers it has acquired for B-52s to incorporate recent design improvements which are expected to make these trailers easier to operate and less costly to support. GAO believes Air Force requirements for new trailers may be overstated by as many asmore » 39 trailers. This could result in the unnecessary expenditure of up to $13 million. GAO also questions the cost effectiveness of remanufacturing the 80 trailers, which would cost $20 million.« less

  13. Interpretation of physiological indicators of motivation: Caveats and recommendations.

    PubMed

    Richter, Michael; Slade, Kate

    2017-09-01

    Motivation scientists employing physiological measures to gather information about motivation-related states are at risk of committing two fundamental errors: overstating the inferences that can be drawn from their physiological measures and circular reasoning. We critically discuss two complementary approaches, Cacioppo and colleagues' model of psychophysiological relations and construct validation theory, to highlight the conditions under which these errors are committed and provide guidance on how to avoid them. In particular, we demonstrate that the direct inference from changes in a physiological measure to changes in a motivation-related state requires the demonstration that the measure is not related to other relevant psychological states. We also point out that circular reasoning can be avoided by separating the definition of the motivation-related state from the hypotheses that are empirically tested. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. THE ROLE OF LOCATION IN EVALUATING RACIAL WAGE DISPARITY.

    PubMed

    Black, Dan A; Kolesnikova, Natalia; Sanders, Seth G; Taylor, Lowell J

    2013-05-01

    A standard object of empirical analysis in labor economics is a modified Mincer wage function in which an individual's log wage is specified to be a function of education, experience, and an indicator variable identifying race. We analyze this approach in a context in which individuals live and work in different locations (and thus face different housing prices and wages). Our model provides a justification for the traditional approach, but with the important caveat that the regression should include location-specific fixed effects. Empirical analyses of men in U.S. labor markets demonstrate that failure to condition on location causes us to (i) overstate the decline in black-white wage disparity over the past 60 years, and (ii) understate racial and ethnic wage gaps that remain after taking into account measured cognitive skill differences that emerge when workers are young.

  15. Something from nothing: Estimating consumption rates using propensity scores, with application to emissions reduction policies

    PubMed Central

    Büchs, Milena; Schnepf, Sylke V.

    2017-01-01

    Consumption surveys often record zero purchases of a good because of a short observation window. Measures of distribution are then precluded and only mean consumption rates can be inferred. We show that Propensity Score Matching can be applied to recover the distribution of consumption rates. We demonstrate the method using the UK National Travel Survey, in which c.40% of motorist households purchase no fuel. Estimated consumption rates are plausible judging by households’ annual mileages, and highly skewed. We apply the same approach to estimate CO2 emissions and outcomes of a carbon cap or tax. Reliance on means apparently distorts analysis of such policies because of skewness of the underlying distributions. The regressiveness of a simple tax or cap is overstated, and redistributive features of a revenue-neutral policy are understated. PMID:29020029

  16. Using marketing muscle to sell fat: the rise of obesity in the modern economy.

    PubMed

    Zimmerman, Frederick J

    2011-01-01

    The large increase in obesity in the past 30 years has often been explained in rational choice terms; for example, a decline in food prices has engendered greater food consumption. On closer examination, this kind of explanation does not fit the facts of the current obesity epidemic. Instead, an unprecedented expansion in the scope, power, and ubiquity of food marketing has coincided with an unprecedented expansion in food consumption in predictable ways. Ongoing protestations that the causes of the recent increase in obesity are unknown may overstate the case. Ample evidence indicates that the obesity epidemic is, at least to a large degree, the result of increased marketing power over the American diet. Only by reigning in or countering marketing power can rationality be restored to the dietary choices of Americans.

  17. The implications of selective attrition for estimates of intergenerational elasticity of family income

    PubMed Central

    Schoeni, Robert F.

    2015-01-01

    Numerous studies have estimated a high intergenerational correlation in economic status. Such studies do not typically attend to potential biases that may arise due to survey attrition. Using the Panel Study of Income Dynamics – the data source most commonly used in prior studies – we demonstrate that attrition is particularly high for low-income adult children with low-income parents and particularly low for high-income adult children with high-income parents. Because of this pattern of attrition, intergenerational upward mobility has been overstated for low-income families and downward mobility has been understated for high-income families. The bias among low-income families is greater than the bias among high-income families implying that intergenerational elasticity in family income is higher than previous estimates with the Panel Study of Income Dynamics would suggest. PMID:26251655

  18. Found in Translation: Applying Lessons from Model Systems to Strigolactone Signaling in Parasitic Plants.

    PubMed

    Lumba, Shelley; Subha, Asrinus; McCourt, Peter

    2017-07-01

    Strigolactones (SLs) are small molecules that act as endogenous hormones to regulate plant development as well as exogenous cues that help parasitic plants to infect their hosts. Given that parasitic plants are experimentally challenging systems, researchers are using two approaches to understand how they respond to host-derived SLs. The first involves extrapolating information on SLs from model genetic systems to dissect their roles in parasitic plants. The second uses chemicals to probe SL signaling directly in the parasite Striga hermonthica. These approaches indicate that parasitic plants have co-opted a family of α/β hydrolases to perceive SLs. The importance of this genetic and chemical information cannot be overstated since parasitic plant infestations are major obstacles to food security in the developing world. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Substance Use Disorder Counselors’ Job Performance and Turnover after 1 Year: Linear or Curvilinear Relationship?1

    PubMed Central

    Laschober, Tanja C.; de Tormes Eby, Lillian Turner

    2013-01-01

    The main goals of the current study were to investigate whether there are linear or curvilinear relationships between substance use disorder counselors’ job performance and actual turnover after 1 year utilizing four indicators of job performance and three turnover statuses (voluntary, involuntary, and no turnover as the reference group). Using longitudinal data from 440 matched counselor-clinical supervisor dyads, results indicate that overall, counselors with lower job performance are more likely to turn over voluntarily and involuntarily than not to turn over. Further, one of the job performance measures shows a significant curvilinear effect. We conclude that the negative consequences often assumed to be “caused” by counselor turnover may be overstated because those who leave both voluntarily and involuntarily demonstrate generally lower performance than those who remain employed at their treatment program. PMID:22527711

  20. Substance use disorder counselors' job performance and turnover after 1 year: linear or curvilinear relationship?

    PubMed

    Laschober, Tanja C; de Tormes Eby, Lillian Turner

    2013-07-01

    The main goals of the current study were to investigate whether there are linear or curvilinear relationships between substance use disorder counselors' job performance and actual turnover after 1 year utilizing four indicators of job performance and three turnover statuses (voluntary, involuntary, and no turnover as the reference group). Using longitudinal data from 440 matched counselor-clinical supervisor dyads, results indicate that overall, counselors with lower job performance are more likely to turn over voluntarily and involuntarily than not to turn over. Further, one of the job performance measures shows a significant curvilinear effect. We conclude that the negative consequences often assumed to be "caused" by counselor turnover may be overstated because those who leave both voluntarily and involuntarily demonstrate generally lower performance than those who remain employed at their treatment program.

  1. Hydraulic concentration of magnetic fields in the solar photosphere. III - Fields of one or two kilogauss

    NASA Technical Reports Server (NTRS)

    Parker, E. N.

    1976-01-01

    Detailed analysis of weak and strong lines suggests that the magnetic fields in isolated intense flux tubes in supergranule boundaries in the solar photosphere may be as large as 2000 gauss. This paper is a concise systematic review of hydrodynamic effects that might compress a magnetic field to great intensity. The properties of force-free fields are reviewed to show that they do not contribute to concentration of magnetic fields, in spite of the popular notion to the contrary. Of the seven effects considered, it is concluded that only cooling of the gas within the field can produce the high field densities inferred from observation. It is shown that inhibition of convection appears not to possess the necessary qualitative cooling features and that overstability, generating transverse hydromagnetic waves - essentially Alfven waves - is the only way to account for the cooling and field intensification.

  2. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wheeler, Douglas; Ulsh, Michael

    The results of two Manufacturing Readiness Assessments of PEM fuel cell stacks and material handling equipment (MHE) and backup power (BUP) PEM fuel cell systems are given. Design modifications of fuel cell systems were made because the initial, 2008 designs did not fully meet the operational requirements of the markets. This situation indicates the 2008 risk elements were overstated.For 2010 BUP and MHE fuel cell systems, manufacturers had not reached the Low Rate Initial Production (LRIP) defined in the 2008 MRA Report at 1,000 units per year per manufacturer.For fuel cell stacks, LRIP was demonstrated by more than one manufacturer.Themore » federal tax incentive program has compensated for the initial high cost of fuel cell systems.The Balance-of-Plant (BOP) has not evolved as rapidly as the PEM fuel cell stack manufacturing readiness.The BOP in 2014 is as costly as the fuel cell stack for MHE applications.« less

  3. Consumer beware: a systematic assessment of potential bias in the lay electronic media to examine the portrayal of "PARP" inhibitors for cancer treatment.

    PubMed

    Coleman, Shawnta; Peethambaram, Prema P; Jatoi, Aminah

    2011-09-01

    This study examined how the lay electronic media covers poly-ADP-ribose polymerase, or "PARP," inhibitors, a class of cancer agents currently under clinical investigation. Of 771 internet links, 51 targeted the lay public. Independent review by two investigators yielded the following categorizations: 36 (71%) were "overly positive", 15 (29%) "neutral", and none "overly negative". "Overly positive" articles used: (l) overstated benefit, (2) included quotations from enthusiastic scientists, and (3) discussed single or small patient subsets. They used such phrases as "the holy grail of cancer research", "the most exciting development in cancer research in a decade or more…. it could save thousands of lives", and "we were surprised and delighted…. it's the kind of thing you don't really think will happen". Healthcare providers should be aware of the foregoing when discussing PARP inhibitors-and perhaps other novel therapies-with cancer patients.

  4. Science in liquid dietary supplement promotion: the misleading case of mangosteen juice.

    PubMed

    Lobb, Ano L

    2012-02-01

    Liquid dietary supplements represent a fast growing market segment, including botanically-based beverages containing mangosteen, acai, and noni. These products often resemble fruit juice in packaging and appearance, but may contain pharmacologically active ingredients. While little is known about the human health effects or safety of consuming such products, manufacturers make extensive use of low-quality published research to promote their products. This report analyzes the science-based marketing claims of two of the most widely consumed mangosteen liquid dietary supplements, and compares them to the findings of the research being cited. The reviewer found that analyzed marketing claims overstate the significance of findings, and fail to disclose severe methodological weaknesses of the research they cite. If this trend extends to other related products that are similarly widely consumed, it may pose a public health threat by misleading consumers into assuming that product safety and effectiveness are backed by rigorous scientific data.

  5. Instrumenting Beliefs in Threshold Public Goods

    PubMed Central

    2016-01-01

    Understanding the causal impact of beliefs on contributions in Threshold Public Goods (TPGs) is particularly important since the social optimum can be supported as a Nash Equilibrium and best-response contributions are a function of beliefs. Unfortunately, investigations of the impact of beliefs on behavior are plagued with endogeneity concerns. We create a set of instruments by cleanly and exogenously manipulating beliefs without deception. Tests indicate that the instruments are valid and relevant. Perhaps surprisingly, we fail to find evidence that beliefs are endogenous in either the one-shot or repeated-decision settings. TPG allocations are determined by a base contribution and beliefs in a one shot-setting. In the repeated-decision environment, once we instrument for first-round allocations, we find that second-round allocations are driven equally by beliefs and history. Moreover, we find that failing to instrument prior decisions overstates their importance. PMID:26859492

  6. Group rationale, collective sense: beyond intergroup bias.

    PubMed

    Spears, Russell

    2010-03-01

    In this paper, I contest the view of the group as a source of bias and irrationality, especially prevalent within social psychology. I argue that this negative evaluation often arises by applying inappropriate standards, relating to the wrong level of analysis (often the individual level). Second, the image of the group as bad and biasing is often overstated. For example, the evidence suggests that intergroup discrimination, rather than being universal or generic, is often constrained, proportionate and reflects functional and rational strategies for managing threats and opportunities at the group level. Third, although the recent upsurge of interest in group emotions could be seen to reinforce the dualism between rationality and emotion, the contemporary functional approach argues for group emotions as augmenting rather than contradicting rationality. However, we should be wary (and weary) of narrow economic and individualist notions of rationality; group identity may offer the opportunity to redefine rationality in more collective and prosocial ways.

  7. Reflexivity over and above convention: the new orthodoxy in the sociology of personal life, formerly sociology of the family.

    PubMed

    Gilding, Michael

    2010-12-01

    There is a new orthodoxy in the field that was once understood as the sociology of the family, and is increasingly understood as the sociology of 'personal life', 'intimacy', 'relationships' and 'families'. The orthodoxy highlights the open-endedness of intimate relations at the expense of the family as an institution; that is, reflexivity over and above convention. This article argues that the new orthodoxy not only overstates reflexivity at the expense of convention, but abdicates understanding to frameworks grounded in biologistic and economistic understandings of human behaviour. The article makes its point through attention to three areas of research at odds with the new orthodoxy: paternity uncertainty, inheritance and family business. It then proposes that conceptualization of the family as an institutional regime gives due weight to the reflexive reconfiguration of family relationships and practices on the one hand, and their institutional embeddedness on the other.

  8. TASER® conducted electrical weapons: misconceptions in the scientific/medical and other literature.

    PubMed

    Jauchem, James R

    2015-03-01

    TASER(®) conducted electrical weapons (CEWs) have become an important law-enforcement tool. Controversial questions are often raised during discussion of some incidents in which the devices have been used. The main purpose of this paper is to point out some misconceptions about CEWs that have been published in the scientific/medical and other literature. This is a narrative review, using a multidisciplinary approach of analyzing reports from scientific/medical and other literature sources. In previous reports, durations of incapacitating effects and possible associations of CEWs with deaths-in-custody have often been overstated or exaggerated. Comparisons of CEW effects with "electrocution" are misleading. Clarification of these misconceptions may be important during policymaker decisions, practitioner operations, expert witness testimonies, and court proceedings. Despite misconceptions in the literature, CEWs can still be a valuable tool for law enforcement activities. Scientists, medical professionals, legal advisors, and investigators of police tactics should be aware of these misconceptions.

  9. Repeating the Past: Prevention Focus Motivates Repetition, Even For Unethical Decisions

    PubMed Central

    Zhang, Shu; Cornwell, James F.M.; Higgins, E. Tory

    2013-01-01

    Prevention-focused individuals are motivated to maintain the status quo. Given this, we predicted that individuals with a strong prevention focus, either as a chronic predisposition or situationally induced, would treat their initial decision of how to behave on a first task as the status quo, and thus be motivated to repeat that decision on a subsequent task—even for decisions that are ethically questionable. Five studies supported this prediction in multiple ethical domains: whether or not to overstate performance (Studies 1, 2a, 2b), to disclose disadvantageous facts (Study 3), and to pledge a donation (Study 4). The prevention-repetition effect was observed when initial and subsequent decisions were in the same domain (Studies 1-3) and in different domains (Study 4). Alternative accounts such as justification for the initial decision and preference for consistency were ruled out (Study 2b). PMID:24277774

  10. Justification bias in self-reported disability: New evidence from panel data.

    PubMed

    Black, Nicole; Johnston, David W; Suziedelyte, Agne

    2017-07-01

    The relationship between health and work is frequently investigated using self-assessments of disability from social surveys. The complication is that respondents may overstate their level of disability to justify non-employment and welfare receipt. This study provides new evidence on the existence and magnitude of justification bias by exploiting a novel feature of a large longitudinal survey: each wave respondents are asked identical disability questions twice; near the beginning and end of the face-to-face interview. Prior to answering the second disability question, respondents are asked a series of questions that increase the salience of their employment and welfare circumstances. Justification bias is identified by comparing the variation between the two measures within-individuals over time, with the variation in employment status over time. Results indicate substantial and statistically significant justification bias; especially for men and women who receive disability pensions. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Magnetosheath lion roars

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Smith, E.J.; Tsurutani, B.T.

    1976-05-01

    Lion roars, which are intense packets of electromagnetic waves characteristically found in the magneosheath, have been studied. On the basis of these observations, several possible wave generation mechanisms are examined. Landau resonance is considered to be an unlikely source because this mechanism requires a substantial component of the wave electric field paralle to B, and the observation that the waves propagate along the ambient field is contrary to this requirement. It is not obvious that electron cyclotron resonance is responsible, because the field magnitude decreases should cause T/sub parallel//T/sub perpendicular/ to increase, and this rise could lead to wave dampingmore » rather than wave growth. A model which is consistent with all the observations of this study is a proton cyclotron overstability involving 10-keV protons streaming through the magnetosheath. It appears possible that the streaming protons could produce both the waves and the field decreases and that all three would be coincident. (AIP)« less

  12. Personal responsibility and control over our bodies: when expectation exceeds reality.

    PubMed

    Brownell, K D

    1991-01-01

    Good health has become more than a means to personal goals such as greater attractiveness and increased longevity. It symbolizes self-control, hard work, ambition, and success in life. Inherent in this symbolism is the concept that the individual controls behavior, which in turn controls health. Although control over one's life plays an important role in both physical and mental health, the concept of personal control also infers responsibility. Positive attributes are accorded to people who are healthy, but those who fall ill, or those with less than the perfect body, are blamed and are thought to be self-indulgent, lazy, or even irresponsible and immoral. There is a tendency to overstate the impact of personal behavior on health. However, biological realities shape the degree to which health is under the control of the individual. The positive effects of behavior change must be balanced with the limits imposed by biology.

  13. Assisted reproductive technologies and children's neurodevelopmental outcomes.

    PubMed

    Hediger, Mary L; Bell, Erin M; Druschel, Charlotte M; Buck Louis, Germaine M

    2013-02-01

    Initial reports suggested that children conceived with assisted reproductive technologies (ART) may be at increased risk for a spectrum of developmental disabilities. Evolving evidence suggests that some of the early risks may have been overstated when not taking plurality of birth or gestational age at delivery into consideration, as both are independent risk factors for neurodevelopmental disabilities arising from alterations in structure and function or limitations in activities. Continued research is needed to overcome lingering data gaps in light of the equivocal literature for many neurodevelopmental disabilities relative to ART, increasing utilization of services, and changes in the clinical management of infecund couples such as the adoption of natural cycles or in vitro maturation treatment options. Population-based cohorts with longitudinal assessment of the multifaceted nature of neurodevelopment across critical and sensitive windows is paramount for the development of empirically based guidance for clinical and population health. Copyright © 2013 American Society for Reproductive Medicine. All rights reserved.

  14. "Medical effectiveness" in Canadian and U.S. health policy: the comparative politics of inferential ambiguity.

    PubMed Central

    Tanenbaum, S J

    1996-01-01

    OBJECTIVE: To compare Canadian and U.S. policymaking to determine how different health care systems may use health services research differently in responding to the common problem of ineffective medical care. DATA SOURCES/STUDY DESIGN/DATA COLLECTION: Not applicable. PRINCIPAL FINDINGS: The United States and Canada are making surprisingly divergent responses to the problem of medical ineffectiveness: reinforcement of the solidarity principle and deprivatization in Canada, and reinforcement of market competition and privatization in the United States. In doing so, Canadian policymakers overstate the societal applicability and U.S. policymakers the individual applicability of outcomes research findings. CONCLUSIONS: Probabilistic findings of medical effectiveness are fundamentally ambiguous as they relate to action. They therefore invite divergent policy responses from different policy regimes. Health services researchers must not imagine that research findings are sufficient to determine the course of health policy. PMID:8943988

  15. Are people who claim compensation "cured by a verdict"? A longitudinal study of health outcomes after whiplash.

    PubMed

    Spearing, Natalie M; Gyrd-Hansen, Dorte; Pobereskin, Louis H; Rowell, David S; Connelly, Luke B

    2012-09-01

    This study examines whether the lure of injury compensation prompts whiplash claimants to overstate their symptoms. Claim settlement is the intervention of interest, as it represents the point at which there is no further incentive to exaggerate symptoms, and neck pain at 24 months is the outcome of interest. Longitudinal data on neck pain scores and timing of claim settlement were regressed, controlling for the effect of time on recovery, to compare outcomes in claimants who had and had not settled their compensation claims. The results show clearly that removing the financial incentive to over-report symptoms has no effect on self-reported neck pain in a fault-based compensation scheme, and this finding concurs with other studies on this topic. Policy decisions to limit compensation in the belief that claimants systematically misrepresent their health status are not supported empirically Claimants do not appear to be "cured by a verdict".

  16. Effects of core sealing methods on the preservation of pore water

    USGS Publications Warehouse

    Striffler, Pete; Peters, Charles A.

    1993-01-01

    Five general core sealing methods (using Protecore, Lexan, wax, Protecore with wax, and Protecore with Lexan) were studied over a two year period to determine their moisture retention capabilities. Results indicate that the multibarrier methods (Protecore with wax and Protecore with Lexan) and the single barrier methods (Protecore and wax) provide successful means of retaining moisture in cores. Additional testing indicated that a tight wrap of Saran is effective in: 1) protecting the outer vapor barriers from puncture, 2) containing any condensate in close proximity to where it was condensed, and 3) retarding condensation. Tests conducted to determine the moisture adsorption potential of wax and the use of applying a positive or negative pressure to Protecore packets proved inconclusive, but warrant further investigation. The importance of proper and timely handling of core samples in the field, including refrigeration and weighing of samples, can not be overstated.

  17. Investigation of temperature and concentration oscillations in the directional solidification of Pb-Sn-Te

    NASA Technical Reports Server (NTRS)

    Anderson, T. J.; Narayanan, R.

    1987-01-01

    Directional solidification of the pseudobinary compound semiconductor material Pb sub 1-x Sn sub x Te by the Bridgman crystal growth process will be studied. Natural convection in the molten sample will be visualized with a novel electrochemical cell technique that employs the solid electrolyte material yttria-stabilized zirconia. Mass transfer by both diffusion and convection will be measured by detecting the motion of oxygen tracer in the liquid. Additional applications for electrochemical cells in semiconductor crystal growth are suggested. Unsteady convection in the melt will also be detected by the appearance of temperature oscillations. The purpose of this study is to experimentally characterize the overstable conditions for a Pb sub 1-x Sn sub x Te melt in the vertical Bridgman crystal growth technique and use a linear analysis to predict the onset of convection for this system.

  18. THE ROLE OF LOCATION IN EVALUATING RACIAL WAGE DISPARITY

    PubMed Central

    Black, Dan A.; Kolesnikova, Natalia; Sanders, Seth G.; Taylor, Lowell J.

    2015-01-01

    A standard object of empirical analysis in labor economics is a modified Mincer wage function in which an individual’s log wage is specified to be a function of education, experience, and an indicator variable identifying race. We analyze this approach in a context in which individuals live and work in different locations (and thus face different housing prices and wages). Our model provides a justification for the traditional approach, but with the important caveat that the regression should include location-specific fixed effects. Empirical analyses of men in U.S. labor markets demonstrate that failure to condition on location causes us to (i) overstate the decline in black-white wage disparity over the past 60 years, and (ii) understate racial and ethnic wage gaps that remain after taking into account measured cognitive skill differences that emerge when workers are young. PMID:25798025

  19. The right paperwork for the right audiences.

    PubMed

    Lyons, M F

    2001-01-01

    Physician executives need to exercise considerable discretion, care, and judgment when they write about their professional accomplishments in the form of a résumé or curriculum vitae (CV). This paperwork is intensely personal. It must be a true reflection of you, your achievements and goals. Others read it to learn more about you. Those you fail to convince, you're likely to lose--along with your chance to meet and charm them in a personal interview. A physician executive's thoughtfully prepared résumé and CV can result in him or her being offered terrific opportunities for career growth. The paperwork is a self-constructed gateway through which you can properly approach hiring organizations--and how it reads is totally under your control. Some suggestions to consider in developing your résumé or CV are: be succinct; don't overstate; use both documents; do your homework; and be ready for the next steps.

  20. What U.S. Data Should be Used to Measure the Price Elasticity of Demand for Alcohol?*

    PubMed Central

    Ruhm, Christopher J.; Jones, Alison Snow; McGeary, Kerry Anne; Kerr, William C.; Terza, Joseph V.; Greenfield, Thomas K.; Pandian, Ravi S.

    2012-01-01

    This paper examines how estimates of the price elasticity of demand for beer vary with the choice of alcohol price series examined. Our most important finding is that the commonly used ACCRA price data are unlikely to reliably indicate alcohol demand elasticities—estimates obtained from this source vary drastically and unpredictably. As an alternative, researchers often use beer taxes to proxy for alcohol prices. While the estimated beer taxes elasticities are more stable, there are several problems with using taxes, including difficulties in accounting for cross-price effects. We believe that the most useful estimates reported in this paper are obtained using annual Uniform Product Code (UPC) “barcode” scanner data on grocery store alcohol prices. These estimates suggest relatively low demand elasticity, probably around −0.3, with evidence that the elasticities are considerably overstated in models that control for beer but not wine or spirits prices. PMID:23022631

  1. Exploring The Relation Between Upper Tropospheric (UT) Clouds and Convection

    NASA Astrophysics Data System (ADS)

    Stephens, G. L.; Stubenrauch, C.

    2017-12-01

    The importance of knowing the vertical transports of water vapor and condensate by atmospheric moist convection cannot be overstated. Vertical convective transports have wide-ranging influences on the Earth system, shaping weather, climate, the hydrological cycle and the composition of the atmosphere. These transports also influence the upper tropospheric cloudiness that exerts profound effects on climate. Although there are presently no direct observations to quantify these transports on the large scale, and there are no observations to constrain model assumptions about them, it might be possible to derive useful observations proxies of these transports and their influence. This talk will present results derived from a large community effort that has developed important observations data records that link clouds and convection. Steps to use these observational metrics to examine the relation between convection, UT clouds in both cloud and global scale models are exemplified and important feedbacks between high clouds, radiation and convection will be elucidated.

  2. Dual-Process Theories of Higher Cognition: Advancing the Debate.

    PubMed

    Evans, Jonathan St B T; Stanovich, Keith E

    2013-05-01

    Dual-process and dual-system theories in both cognitive and social psychology have been subjected to a number of recently published criticisms. However, they have been attacked as a category, incorrectly assuming there is a generic version that applies to all. We identify and respond to 5 main lines of argument made by such critics. We agree that some of these arguments have force against some of the theories in the literature but believe them to be overstated. We argue that the dual-processing distinction is supported by much recent evidence in cognitive science. Our preferred theoretical approach is one in which rapid autonomous processes (Type 1) are assumed to yield default responses unless intervened on by distinctive higher order reasoning processes (Type 2). What defines the difference is that Type 2 processing supports hypothetical thinking and load heavily on working memory. © The Author(s) 2013.

  3. Climate change and human health: the role of nurses in confronting the issue.

    PubMed

    Sayre, Lucia; Rhazi, Nadia; Carpenter, Holly; Hughes, Nancy L

    2010-01-01

    Climate change will impact human health in various ways as the ecology of our planet changes. Environmental changes such as increased heat waves, sea-level rise, and increased drought around the globe will aggravate already-existing health problems, increase the onset of new health problems, and, in some cases, cause premature death. Catastrophic events associated with these environmental changes, such as floods, and increases in hospital and routine clinic visits will have nurses on the front lines tending to those in need. Climate change needs to be reframed as a public health issue, and the importance of nurses to be educated and engaged cannot be overstated. Nurses can be instrumental in communications with patients and families, working with their hospitals and health systems to reduce emissions and influencing the adoption of strategies to better prepare our health care facilities and our communities for the health impacts of climate change.

  4. Spent fuel cask handling at an operating nuclear power plant

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pal, A.C.

    1988-01-01

    The importance of spent fuel handling at operating nuclear power plants cannot be overstated. Because of its highly radioactive nature, however, spent fuel must be handled in thick, lead-lined containers or casks. Thus, all casks for spent fuel handling are heavy loads by the US Nuclear Regulatory Commission's definition, and any load-drop must be evaluated for its potential to damage safety-related equipment. Nuclear Regulatory Guide NUREG-0612 prescribes the regulatory requirements of alternative heavy-load-handling methodologies such as (a) by providing cranes that meet the requirements of NUREG-0554, which shall be called the soft path, or (b) by providing protective devices atmore » all postulated load-drop areas to prevent any damage to safety-related equipment, which shall be called the hard path. The work reported in this paper relates to cask handling at New York Power Authority's James A. FitzPatrick (JAF) plant.« less

  5. Breaking mean-motion resonances during Type I planet migration

    NASA Astrophysics Data System (ADS)

    Hands, T. O.; Alexander, R. D.

    2018-03-01

    We present 2D hydrodynamical simulations of pairs of planets migrating simultaneously in the Type I regime in a protoplanetary disc. Convergent migration naturally leads to the trapping of these planets in mean-motion resonances. Once in resonance the planets' eccentricity grows rapidly, and disc-planet torques cause the planets to escape resonance on a time-scale of a few hundred orbits. The effect is more pronounced in highly viscous discs, but operates efficiently even in inviscid discs. We attribute this resonance-breaking to overstable librations driven by moderate eccentricity damping, but find that this mechanism operates differently in hydrodynamic simulations than in previous analytic calculations. Planets escaping resonance in this manner can potentially explain the observed paucity of resonances in Kepler multitransiting systems, and we suggest that simultaneous disc-driven migration remains the most plausible means of assembling tightly packed planetary systems.

  6. On Thermal Instability of Kuvshiniski Fluid with Suspended Particles Saturated in a Porous Medium in the Presence of a Magnetic Field June 13, 2017

    NASA Astrophysics Data System (ADS)

    Singh, M.

    2017-12-01

    The thermal instability of a Kuvshiniski viscoelastic fluid is considered to include the effects of a uniform horizontal magnetic field, suspended particles saturated in a porous medium. The analysis is carried out within the framework of the linear stability theory and normal mode technique. For the case of stationary convection, the Kuvshiniski viscoelastic fluid behaves like a Newtonian fluid and the magnetic field has a stabilizing effect, whereas medium permeability and suspended particles are found to have a destabilizing effect on the system, oscillatory modes are introduced in the system, in the absence of these the principle of exchange of stabilities is valid. Graphs in each case have been plotted by giving numerical values to the parameters, depicting the stability characteristics. Sufficient conditions for the avoidance of overstability are also obtained.

  7. Stability Analysis and Internal Heating Effect on Oscillatory Convection in a Viscoelastic Fluid Saturated Porous Medium Under Gravity Modulation

    NASA Astrophysics Data System (ADS)

    Bhadauria, B. S.; Singh, M. K.; Singh, A.; Singh, B. K.; Kiran, P.

    2016-12-01

    In this paper, we investigate the combined effect of internal heating and time periodic gravity modulation in a viscoelastic fluid saturated porous medium by reducing the problem into a complex non-autonomous Ginzgburg-Landau equation. Weak nonlinear stability analysis has been performed by using power series expansion in terms of the amplitude of gravity modulation, which is assumed to be small. The Nusselt number is obtained in terms of the amplitude for oscillatory mode of convection. The influence of viscoelastic parameters on heat transfer has been discussed. Gravity modulation is found to have a destabilizing effect at low frequencies and a stabilizing effect at high frequencies. Finally, it is found that overstability advances the onset of convection, more with internal heating. The conditions for which the complex Ginzgburg-Landau equation undergoes Hopf bifurcation and the amplitude equation undergoes supercritical pitchfork bifurcation are studied.

  8. Population ageing: what should we worry about?

    PubMed Central

    Turner, Adair

    2009-01-01

    Approximately half the world's population now has replacement-level fertility or below. The UK experience in accommodating to a changing dependency ratio provides some generalizable insights. A mechanistic approach assuming a fixed retirement age and a need to raise fertility or increase immigration in order to maintain pensions at a fixed proportion of the gross domestic product (GDP) is overstated and wrong. It needs to be replaced by a welfare optimizing model, which takes into account the increasing years of healthy life, a slow rise in the pensionable age, capital inheritance and wider welfare considerations of population density that are not reflected in GDP measures. A combined replacement ratio (CRR) is suggested for developed countries combining the impact of the fertility rate and immigration rate. A CRR above 2 implies continued population growth. The current UK CRR of 2.48 is higher than needed for pension reasons, and it is suggested that it exceeds the welfare maximizing level. PMID:19770152

  9. The extent of physician participation in Medicaid: a comparison of physician estimates and aggregated patient records.

    PubMed Central

    Kletke, P R; Davidson, S M; Perloff, J D; Schiff, D W; Connelly, J P

    1985-01-01

    This article compares two measures of the extent of physician participation in Medicaid programs. The first, which has been used in most research to date on the subject, is based on physician estimates of the proportion of their patients who are Medicaid patients. The second derives from encounter forms for a sample of visits to the interviewed physicians. The comparison shows that physicians in the sample tended to overestimate by 40 percent the extent of their Medicaid participation. Because the two measures are highly correlated, the analysis of the determinants of Medicaid participation was not affected by the measure used. However, since physicians tended to overstate the proportion of Medicaid patients in their practices, interview data should not be used to measure the amount of physician participation or to calculate elasticities for the effects of policy changes on the extent of participation. PMID:3910615

  10. Timber harvest calculations on a National Forest: A case study

    NASA Astrophysics Data System (ADS)

    Carey, Henry H.

    1983-03-01

    Harvest calculations determine sawtimber flows from public lands and are closely scruntinized by a wide spectrum of forest users. This study examines the reliability of harvest calculations on a single national forest in New Mexico Forest Service determinations of an array of variables were reviewed and evaluated. The study revealed a lack of precision in Forest Service adherence to self-imposed procedural standards governing the calculation process. Timber sales have taken place on lands where such standards prohibit harvesting and these lands have been included in annual harvest calculations. Assumptions required by a mathematical model used by the Forest Service in calculating the harvest were not followed in the subsequent implementation of the harvest level. These factors suggest that the Forest Service could have significantly over-stated annual harvest rate for the first decade. Opportunities exist to improve the calculation, and benefits realized may greatly exceed additional costs of implementation

  11. Hazards to wildlife from soil-borne cadmium reconsidered

    USGS Publications Warehouse

    Beyer, W.N.

    2000-01-01

    Cadmium is a toxic element that should be included in environmental risk assessments of contaminated soils. This paper argues, however, that hazards to wildlife from cadmium have often been overstated. The literature contains only meager evidence that wild animals have been seriously harmed by cadmium, even at severely contaminated sites. Although some researchers have reported that wildlife have accumulated concentrations of cadmium in their kidneys that were above suggested injury thresholds, the thresholds may be disputed, since they were well below the World Health Organization criterion of 200 mg/kg (wet weight) of cadmium in the renal cortex for protecting human health. Recent risk assessments have concluded that soil cadmium concentrations less than 1 mg/kg are toxic to soil organisms and wildlife, which implies that background concentrations of cadmium naturally found in soils are hazardous. An examination of the databases used to support these assessments suggested that the toxicity of cadmium has been exaggerated.

  12. Science in Liquid Dietary Supplement Promotion: The Misleading Case of Mangosteen Juice

    PubMed Central

    2012-01-01

    Liquid dietary supplements represent a fast growing market segment, including botanically-based beverages containing mangosteen, acai, and noni. These products often resemble fruit juice in packaging and appearance, but may contain pharmacologically active ingredients. While little is known about the human health effects or safety of consuming such products, manufacturers make extensive use of low-quality published research to promote their products. This report analyzes the science-based marketing claims of two of the most widely consumed mangosteen liquid dietary supplements, and compares them to the findings of the research being cited. The reviewer found that analyzed marketing claims overstate the significance of findings, and fail to disclose severe methodological weaknesses of the research they cite. If this trend extends to other related products that are similarly widely consumed, it may pose a public health threat by misleading consumers into assuming that product safety and effectiveness are backed by rigorous scientific data. PMID:22454810

  13. Viscous pulsational instability of the transonic region of isothermal geometrically thin accretion discs. I - Analytical results

    NASA Astrophysics Data System (ADS)

    Kato, Shoji; Honma, Fumio; Matsumoto, Ryoji

    1988-03-01

    Viscous instability of the transonic region of the conventional geometrically thin alpha-type accretion disks is examined analytically. For simplicity, isothermal disks and isothermal perturbations are assumed. It is found that when the value of alpha is larger than a critical value the disk is unstable against two types of perturbations. One is local propagating perturbations of inertial acoustic waves. Results suggest the possibility that unstable perturbations develop to overstable global oscillations which are restricted only in the innermost region of the disk. The other is standing growing perturbations localized just at the transonic point. The cause of these instabilities is that the azimuthal component of the Lagrangian velocity variation associated with the perturbations becomes in phase with the variation of the viscous stress force. Because of this phase matching work is done on perturbations, and they are amplified.

  14. Regional economic analysis of current and proposed management alternatives for Rappahannock River Valley National Wildlife Refuge

    USGS Publications Warehouse

    Koontz, Lynne; Sexton, Natalie; Donovan, Ryan

    2009-01-01

    The National Wildlife Refuge System Improvement Act of 1997 requires all units of the National Wildlife Refuge System to be managed under a Comprehensive Conservation Plan. The Comprehensive Conservation Plan must describe the desired future conditions of a refuge and provide long-range guidance and management direction to achieve refuge purposes. The Rappahannock River Valley National Wildlife Refuge (refuge) is in the process of developing a range of management goals, objectives, and strategies for the Comprehensive Conservation Plan. The Comprehensive Conservation Plan for the refuge must contain an analysis of expected effects associated with current and proposed refuge management strategies. The purpose of this study was to assess the regional economic implications associated with draft Comprehensive Conservation Plan management strategies. Special interest groups and local residents often criticize a change in refuge management, especially if there is a perceived negative impact to the local economy. Having objective data on economic impacts may show that these fears are overstated. Quite often, the extent of economic benefits a refuge provides to a local community is not fully recognized, yet at the same time the effects of negative changes is overstated. Spending associated with refuge recreational activities, such as wildlife viewing and hunting, can generate considerable tourist activity for surrounding communities. Additionally, refuge personnel typically spend considerable amounts of money purchasing supplies in local stores, repairing equipment and purchasing fuel at the local service stations, and reside and spend their salaries in the local community. For refuge Comprehensive Conservation Plan planning, a regional economic assessment provides a means of estimating how current management (no action alternative) and proposed management activities (alternatives) could affect the local economy. This type of analysis provides two critical pieces of information: (1) it illustrates a refuge's contribution to the local community; and (2) it can help in determining whether local economic effects are or are not a real concern in choosing among management alternatives. It is important to note that the economic value of a refuge encompasses more than just the impacts of the regional economy. Refuges also provide substantial nonmarket values (values for items not exchanged in established markets), such as maintaining endangered species, preserving wetlands, educating future generations, and adding stability to the ecosystem. However, quantifying these types of nonmarket values was beyond the scope of this study because of time and budget constraints.

  15. Integrating science, economics and law into policy: The case of carbon sequestration in climate change policy

    NASA Astrophysics Data System (ADS)

    Richards, Kenneth

    Carbon sequestration, the extraction and storage of carbon from the atmosphere by biomass, could potentially provide a cost-effective means to reduce net greenhouse gas emissions. The claims on behalf of carbon sequestration may be inadvertently overstated, however. Several key observations emerge from this study. First, although carbon sequestration studies all report results in terms of dollars per ton, the definition of that term varies significantly, meaning that the results of various analyses can not be meaningfully compared. Second, when carbon sequestration is included in an energy-economy model of climate change policy, it appears that carbon sequestration could play a major, if not dominant role in a national carbon emission abatement program, reducing costs of emissions stabilization by as much as 80 percent, saving tens of billions of dollars per year. However, the results are very dependant upon landowners' perceived risk. Studies may also have overstated the potential for carbon sequestration because they have not considered the implementation process. This study demonstrates that three factors will reduce the cost-effectiveness of carbon sequestration. First, the implementation costs associated with measurement and governance of the government-private sector relation are higher than in the case of carbon source control. Second, legal constraints limit the range of instruments that the government can use to induce private landowners to expand their carbon sinks. The government will likely have to pay private parties to expand their sinks, or undertake direct government production. In either case, additional revenues will be required, introducing social costs associated with excess burden. Third, because of the very long time involved in developing carbon sinks (up to several decades) the government may not be able to make credible commitments against exactions of one type or another that would effectively reduce the value of private sector investments in carbon sinks. Consequently, the private sector will increase the rate of return required for participation, increasing the cost of this option. Carbon sequestration can still be a major factor in a national carbon emission abatement program. However, because of the interplay of science, economics and law, the most commonly prescribed environmental policy instruments--marketable allowance and taxes--have little or no direct role to play in the implementation process.

  16. Applications of nanotechnology in water and wastewater treatment.

    PubMed

    Qu, Xiaolei; Alvarez, Pedro J J; Li, Qilin

    2013-08-01

    Providing clean and affordable water to meet human needs is a grand challenge of the 21st century. Worldwide, water supply struggles to keep up with the fast growing demand, which is exacerbated by population growth, global climate change, and water quality deterioration. The need for technological innovation to enable integrated water management cannot be overstated. Nanotechnology holds great potential in advancing water and wastewater treatment to improve treatment efficiency as well as to augment water supply through safe use of unconventional water sources. Here we review recent development in nanotechnology for water and wastewater treatment. The discussion covers candidate nanomaterials, properties and mechanisms that enable the applications, advantages and limitations as compared to existing processes, and barriers and research needs for commercialization. By tracing these technological advances to the physicochemical properties of nanomaterials, the present review outlines the opportunities and limitations to further capitalize on these unique properties for sustainable water management. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Segmentation of thalamus from MR images via task-driven dictionary learning

    NASA Astrophysics Data System (ADS)

    Liu, Luoluo; Glaister, Jeffrey; Sun, Xiaoxia; Carass, Aaron; Tran, Trac D.; Prince, Jerry L.

    2016-03-01

    Automatic thalamus segmentation is useful to track changes in thalamic volume over time. In this work, we introduce a task-driven dictionary learning framework to find the optimal dictionary given a set of eleven features obtained from T1-weighted MRI and diffusion tensor imaging. In this dictionary learning framework, a linear classifier is designed concurrently to classify voxels as belonging to the thalamus or non-thalamus class. Morphological post-processing is applied to produce the final thalamus segmentation. Due to the uneven size of the training data samples for the non-thalamus and thalamus classes, a non-uniform sampling scheme is pro- posed to train the classifier to better discriminate between the two classes around the boundary of the thalamus. Experiments are conducted on data collected from 22 subjects with manually delineated ground truth. The experimental results are promising in terms of improvements in the Dice coefficient of the thalamus segmentation overstate-of-the-art atlas-based thalamus segmentation algorithms.

  18. Are Survey Respondents Lying about Their Support for Same-Sex Marriage? Lessons from a List Experiment.

    PubMed

    Lax, Jeffrey R; Phillips, Justin H; Stollwerk, Alissa F

    2016-01-01

    Public opinion polls consistently show that a growing majority of Americans support same-sex marriage. Critics, however, raise the possibility that these polls are plagued by social desirability bias, and thereby may overstate public support for gay and lesbian rights. We test this proposition using a list experiment embedded in the 2013 Cooperative Congressional Election Study. List experiments afford respondents an anonymity that allows them to provide more truthful answers to potentially sensitive survey items. Our experiment finds no evidence that social desirability is affecting overall survey results. If there is social desirability in polling on same-sex marriage, it pushes in both directions. Indeed, our efforts provide new evidence that a national opinion majority favors same-sex marriage. To evaluate the robustness of our findings, we analyze a second list experiment, this one focusing on the inclusion of sexual orientation in employment nondiscrimination laws. Again, we find no overall evidence of bias.

  19. Low Reynolds number wind tunnel measurements - The importance of being earnest

    NASA Technical Reports Server (NTRS)

    Mueller, Thomas J.; Batill, Stephen M.; Brendel, Michael; Perry, Mark L.; Bloch, Diane R.

    1986-01-01

    A method for obtaining two-dimensional aerodynamic force coefficients at low Reynolds numbers using a three-component external platform balance is presented. Regardless of method, however, the importance of understanding the possible influence of the test facility and instrumentation on the final results cannot be overstated. There is an uncertainty in the ability of the facility to simulate a two-dimensional flow environment due to the confinement effect of the wind tunnel and the method used to mount the airfoil. Additionally, the ability of the instrumentation to accurately measure forces and pressures has an associated uncertainty. This paper focuses on efforts taken to understand the errors introduced by the techniques and apparatus used at the University of Notre Dame, and, the importance of making an earnest estimate of the uncertainty. Although quantitative estimates of facility induced errors are difficult to obtain, the uncertainty in measured results can be handled in a straightforward manner and provide the experimentalist, and others, with a basis to evaluate experimental results.

  20. More Efficient Sodium Removal by Ultrafiltration Compared to Diuretics in Acute Heart Failure; Underexplored and Overstated.

    PubMed

    Kazory, Amir

    2016-01-01

    Enhanced removal of sodium has often been cited as an advantage of ultrafiltration (UF) therapy over diuretic-based medical treatment in the management of acute decompensated heart failure. However, so far clinical studies have rarely evaluated the precise magnitude of sodium removal, and this assumption is largely based on the physiologic mechanisms and anecdotal observations that predate the contemporary management of heart failure. Recent data suggest that patients treated with UF experience substantial reduction in urinary sodium excretion possibly due to prolonged intravascular volume contraction. Consequently, the efficient sodium extraction through production of isotonic ultrafiltrate can be offset by urine hypotonicity. Based on the limited currently available data, it seems unlikely that the persistent benefits of UF could be solely explained by its greater efficiency in sodium removal. The design of the future studies should include frequent measurements of urine sodium to precisely compare the impact of UF and diuretics on sodium balance. © 2016 S. Karger AG, Basel.

  1. Dietary nitrite and nitrate: a review of potential mechanisms of cardiovascular benefits

    PubMed Central

    Machha, Ajay

    2012-01-01

    Purpose In the last decade, a growing scientific and medical interest has emerged toward cardiovascular effects of dietary nitrite and nitrate; however, many questions concerning their mode of action(s) remain unanswered. In this review, we focus on multiple mechanisms that might account for potential cardiovascular beneficial effects of dietary nitrite and nitrate. Results Beneficial changes to cardiovascular health from dietary nitrite and nitrate might result from several mechanism(s) including their reduction into nitric oxide, improvement in endothelial function, vascular relaxation, and/or inhibition of the platelet aggregation. From recently obtained evidence, it appears that the longstanding concerns about the toxicity of oral nitrite or nitrate are overstated. Conclusion Dietary nitrite and nitrate may have cardiovascular protective effects in both healthy individuals and also those with cardiovascular disease conditions. A role for nitrite and nitrate in nitric oxide biosynthesis and/or in improving nitric oxide bioavailability may eventually provide a rationale for using dietary nitrite and nitrate supplementation in the treatment and prevention of cardiovascular diseases. PMID:21626413

  2. Compensating differentials, labor market segmentation, and wage inequality.

    PubMed

    Daw, Jonathan; Hardie, Jessica Halliday

    2012-09-01

    Two literatures on work and the labor market draw attention to the importance of non-pecuniary job amenities. Social psychological perspectives on work suggest that workers have preferences for a range of job amenities (e.g. Halaby, 2003). The compensating differentials hypothesis predicts that workers navigate tradeoffs among different job amenities such that wage inequality overstates inequality in utility (Smith, 1979). This paper joins these perspectives by constructing a new measure of labor market success that evaluates the degree to which workers' job amenity preferences and outcomes match. This measure of subjective success is used to predict workers' job satisfaction and to test the hypothesis that some degree of labor force inequality in wages is due to preference-based tradeoffs among all job amenities. Findings demonstrate that the new measure predicts workers' job satisfaction and provides evidence for the presence of compensating differentials in the primary and intermediate, but not secondary, labor markets. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. Estimates of Mumps Seroprevalence May Be Influenced by Antibody Specificity and Serologic Method

    PubMed Central

    McGrew, Marcia; Williams, Nobia J.; Sowers, Sun B.; Bellini, William J.; Hickman, Carole J.

    2014-01-01

    Neutralizing antibodies are assumed to be essential for protection against mumps virus infection, but their measurement is labor- and time-intensive. For this reason, enzyme-linked immunosorbent assays (ELISAs) are typically used to measure mumps-specific IgG levels. However, since there is poor correlation between mumps neutralization titers and ELISAs that measure the presence of mumps-specific IgG levels, ELISAs that better correlate with neutralization are needed. To address this issue, we measured mumps antibody levels by plaque reduction neutralization, by a commercial ELISA (whole-virus antigen), and by ELISAs specific for the mumps nucleoprotein and hemagglutinin. The results indicate that differences in the antibody response to the individual mumps proteins could partially explain the lack of correlation among various serologic tests. Furthermore, the data indicate that some seropositive individuals have low levels of neutralizing antibody. If neutralizing antibody is important for protection, this suggests that previous estimates of immunity based on whole-virus ELISAs may be overstated. PMID:24371258

  4. SOME APPLICATIONS OF SEISMIC SOURCE MECHANISM STUDIES TO ASSESSING UNDERGROUND HAZARD.

    USGS Publications Warehouse

    McGarr, A.; ,

    1984-01-01

    Various measures of the seismic source mechanism of mine tremors, such as magnitude, moment, stress drop, apparent stress, and seismic efficiency, can be related directly to several aspects of the problem of determining the underground hazard arising from strong ground motion of large seismic events. First, the relation between the sum of seismic moments of tremors and the volume of stope closure caused by mining during a given period can be used in conjunction with magnitude-frequency statistics and an empirical relation between moment and magnitude to estimate the maximum possible sized tremor for a given mining situation. Second, it is shown that the 'energy release rate,' a commonly-used parameter for predicting underground seismic hazard, may be misleading in that the importance of overburden stress, or depth, is overstated. Third, results involving the relation between peak velocity and magnitude, magnitude-frequency statistics, and the maximum possible magnitude are applied to the problem of estimating the frequency at which design limits of certain underground support equipment are likely to be exceeded.

  5. Observations on personnel dosimetry for radiotherapy personnel operating high-energy LINACs.

    PubMed

    Glasgow, G P; Eichling, J; Yoder, R C

    1986-06-01

    A series of measurements were conducted to determine the cause of a sudden increase in personnel radiation exposures. One objective of the measurements was to determine if the increases were related to changing from film dosimeters exchanged monthly to TLD-100 dosimeters exchanged quarterly. While small increases were observed in the dose equivalents of most employees, the dose equivalents of personnel operating medical electron linear accelerators with energies greater than 20 MV doubled coincidentally with the change in the personnel dosimeter program. The measurements indicated a small thermal neutron radiation component around the accelerators operated by these personnel. This component caused the doses measured with the TLD-100 dosimeters to be overstated. Therefore, the increase in these personnel dose equivalents was not due to changes in work habits or radiation environments. Either film or TLD-700 dosimeters would be suitable for personnel monitoring around high-energy linear accelerators. The final choice would depend on economics and personal preference.

  6. Exploring the Predictors of Organizational Preparedness for Natural Disasters.

    PubMed

    Sadiq, Abdul-Akeem; Graham, John D

    2016-05-01

    There is an extensive body of research on the determinants of disaster preparedness at the individual and household levels. The same cannot be said for the organizational level. Hence, the purpose of this study is to shed light on the predictors of organizational preparedness for natural disasters. Since leaders of organizations have an incentive to overstate their level of preparedness and because surveys of organizational leaders suffer from selection bias and low response rates, we take the novel approach of interviewing employees about the organizations that employ them. Using an online survey, we collected information from a national sample of 2,008 U.S. employees and estimated the predictors of preparedness at the organizational level. We find, among other results, that organization size (facility level) is a consistent predictor of preparedness at the organizational level. We conclude with policy recommendations and outline an agenda for future research on organizational preparedness for natural disasters. © 2015 Society for Risk Analysis.

  7. Education and personalized genomics: deciphering the public's genetic health report

    PubMed Central

    Lamb, Neil E; Myers, Richard M; Gunter, Chris

    2010-01-01

    Where do members of the public turn to understand what genetic tests mean in terms of their own health? Now that genome-wide association studies and complete genome sequencing are widely available, the importance of education in personalized genomics cannot be overstated. Although some media have introduced the concept of genetic testing to better understand health and disease, the public's understanding of the scope and impact of genetic variation has not kept up with the pace of the science or technology. Unfortunately, the likely sources to which the public turn to for guidance – their physician and the media – are often no better prepared. We examine several venues for information, including print and online guides for both lay and health-oriented audiences, and summarize selected resources in multiple formats. We also note on the roadblocks to progress and discuss ways to remove them, as urgent action is needed to connect people with their genomes in a meaningful way. PMID:20161675

  8. Reproducible research: a minority opinion

    NASA Astrophysics Data System (ADS)

    Drummond, Chris

    2018-01-01

    Reproducible research, a growing movement within many scientific fields, including machine learning, would require the code, used to generate the experimental results, be published along with any paper. Probably the most compelling argument for this is that it is simply following good scientific practice, established over the years by the greats of science. The implication is that failure to follow such a practice is unscientific, not a label any machine learning researchers would like to carry. It is further claimed that misconduct is causing a growing crisis of confidence in science. That, without this practice being enforced, science would inevitably fall into disrepute. This viewpoint is becoming ubiquitous but here I offer a differing opinion. I argue that far from being central to science, what is being promulgated is a narrow interpretation of how science works. I contend that the consequences are somewhat overstated. I would also contend that the effort necessary to meet the movement's aims, and the general attitude it engenders would not serve well any of the research disciplines, including our own.

  9. Recessions and health: the impact of economic trends on air pollution in California.

    PubMed

    Davis, Mary E

    2012-10-01

    I explored the hypothesis that economic activity has a significant impact on exposure to air pollution and ultimately human health. I used county-level employment statistics in California (1980-2000), along with major regulatory periods and other controlling factors, to estimate local concentrations of the coefficient of haze, carbon monoxide, and nitrogen dioxide using a mixed regression model approach. The model explained between 33% and 48% of the variability in air pollution levels as estimated by the overall R(2) values. The relationship between employment measures and air pollution was statistically significant, suggesting that air quality improves during economic downturns. Additionally, major air quality regulations played a significant role in reducing air pollution levels over the study period. This study provides important evidence of a role for the economy in understanding human exposure to environmental pollution. The evidence further suggests that the impact of environmental regulations are likely to be overstated when they occur during recessionary periods, and understated when they play out during periods of economic growth.

  10. Abortion misinformation from crisis pregnancy centers in North Carolina.

    PubMed

    Bryant, Amy G; Levi, Erika E

    2012-12-01

    This study assessed the accuracy of medical information provided by crisis pregnancy centers in North Carolina. We performed a secondary data analysis of a "secret shopper survey" performed by a nonprofit organization. Reports from phone calls and visits to crisis pregnancy centers were analyzed for quality and content of medical information provided. Web sites of crisis pregnancy centers in the state were also reviewed. Thirty-two crisis pregnancy centers were contacted. Nineteen of these were visited. Fourteen centers (44%) offered that they "provide counseling on abortion and its risks." Inaccurate information provided included a link between abortion and breast cancer (16%), infertility (26%) and mental health problems (26%). Of the 36 Web sites identified, 31 (86%) provided false or misleading information, including 26 sites (72%) linking abortion to "post-abortion stress." Many crisis pregnancy centers give inaccurate medical information regarding the risks of abortion. Overstating risks stigmatizes abortion, seeks to intimidate women and is unethical. Copyright © 2012 Elsevier Inc. All rights reserved.

  11. Monetary effects on fear conditioning.

    PubMed

    Qu, Chen; Zhang, Aiyi; Chen, Qishan

    2013-04-01

    Previous research has found that the loss of money as a negative secondary reinforcer was as effective as a primary reinforcer during fear conditioning. The purpose of the present study was to explore the effect of monetary gain as a positive secondary reinforcer in fear conditioning. Participants were assigned to a high-reward group or low-reward group. Three kinds of squares prompting non-compensation shock, compensation shock, and no shock were presented. Skin conductance responses (SCRs) and self-ratings were recorded. The results revealed that (a) both SCRs and self-ratings in the compensation shock condition were lower than in the non-compensation shock condition, suggesting that money might block the learning stage of fear conditioning; and (b) a higher ratio of fear reduction was present in self-rating when compared to SCRs, suggesting that people might overstate the utility of money, subjectively. Monetary effects, the effects of different amounts of money, and the differences between subjective and physiological levels are discussed.

  12. A reconsideration of parental and peer influences on adolescent deviance.

    PubMed

    Aseltine, R H

    1995-06-01

    The role of peers in fostering deviant behavior in adolescence is well-documented in the sociological literature, while support for parental influence or "control" theories of deviance is more equivocal. This paper examines the relative influences of parents and peers on adolescent delinquency and marijuana use, using data from a three-wave panel study of youths who were paired with a best friend (N = 435). Covariance structure models based upon polychoric correlations among study variables reveal that friends are indeed the primary source of influence on youths' behavior, but that estimates of influence are grossly overstated in analyses relying upon respondents' perceptions of their friends' behavior. Parental supervision and attachment are weakly related to subsequent delinquency and marijuana use, lending little support to control theories of deviance. Findings reveal that different processes account for the similarities among members of delinquent and drug-using peer groups. Although youths are socialized into delinquent behavior by peers, both selection and socialization influences play important roles in the formation of drug-using peer groups.

  13. Challenges in microbial ecology: building predictive understanding of community function and dynamics

    PubMed Central

    Widder, Stefanie; Allen, Rosalind J; Pfeiffer, Thomas; Curtis, Thomas P; Wiuf, Carsten; Sloan, William T; Cordero, Otto X; Brown, Sam P; Momeni, Babak; Shou, Wenying; Kettle, Helen; Flint, Harry J; Haas, Andreas F; Laroche, Béatrice; Kreft, Jan-Ulrich; Rainey, Paul B; Freilich, Shiri; Schuster, Stefan; Milferstedt, Kim; van der Meer, Jan R; Groβkopf, Tobias; Huisman, Jef; Free, Andrew; Picioreanu, Cristian; Quince, Christopher; Klapper, Isaac; Labarthe, Simon; Smets, Barth F; Wang, Harris; Soyer, Orkun S

    2016-01-01

    The importance of microbial communities (MCs) cannot be overstated. MCs underpin the biogeochemical cycles of the earth's soil, oceans and the atmosphere, and perform ecosystem functions that impact plants, animals and humans. Yet our ability to predict and manage the function of these highly complex, dynamically changing communities is limited. Building predictive models that link MC composition to function is a key emerging challenge in microbial ecology. Here, we argue that addressing this challenge requires close coordination of experimental data collection and method development with mathematical model building. We discuss specific examples where model–experiment integration has already resulted in important insights into MC function and structure. We also highlight key research questions that still demand better integration of experiments and models. We argue that such integration is needed to achieve significant progress in our understanding of MC dynamics and function, and we make specific practical suggestions as to how this could be achieved. PMID:27022995

  14. Canine obesity: an overview.

    PubMed

    Gossellin, J; Wren, J A; Sunderland, S J

    2007-08-01

    Canine patients are generally regarded as being clinically obese when their body weight is at least 15% above ideal. The incidence of obesity in dogs is thought to be in the range of 20-40% of the general population and, since obesity is known to predispose or exacerbate a range of serious medical conditions, its importance cannot be overstated. Management of obesity through dietary restriction and increased exercise is often difficult to achieve and dependent upon owner compliance. Until recently there has been no authorized therapeutic medication available for weight reduction in dogs, and drugs used in people have proved unsuitable. However, with the development of microsomal triglyceride transfer protein inhibitors for canine use, such as dirlotapide, the veterinarian has a novel method with which to augment traditional weight control programmes. This approach has the additional advantage that weight loss is achieved without dietary restriction or change in exercise regimen, providing encouragement for the owner to comply with subsequent dietary and exercise recommendations, thereby increasing the likelihood for long-term success.

  15. Avoiding overstating the strength of forensic evidence: Shrunk likelihood ratios/Bayes factors.

    PubMed

    Morrison, Geoffrey Stewart; Poh, Norman

    2018-05-01

    When strength of forensic evidence is quantified using sample data and statistical models, a concern may be raised as to whether the output of a model overestimates the strength of evidence. This is particularly the case when the amount of sample data is small, and hence sampling variability is high. This concern is related to concern about precision. This paper describes, explores, and tests three procedures which shrink the value of the likelihood ratio or Bayes factor toward the neutral value of one. The procedures are: (1) a Bayesian procedure with uninformative priors, (2) use of empirical lower and upper bounds (ELUB), and (3) a novel form of regularized logistic regression. As a benchmark, they are compared with linear discriminant analysis, and in some instances with non-regularized logistic regression. The behaviours of the procedures are explored using Monte Carlo simulated data, and tested on real data from comparisons of voice recordings, face images, and glass fragments. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

  16. A man of his time: thorstein veblen and the university of chicago darwinists.

    PubMed

    Raymer, Emilie J

    2013-01-01

    The Darwinian economic theory that Thorstein Veblen proposed and refined while he served as a professor of Political Economy at the University of Chicago from 1891 to 1906 should be assessed in the context of the community of Darwinian scientists and social scientists with whom Veblen worked and lived at Chicago. It is important to identify Veblen as a member of this broad community of Darwinian-inclined philosophers, physiologists, geologists, astronomers, and biologists at Chicago because Veblen's involvement with this circle suggests that the possible sources of his engagement with Darwinism extend beyond the pragmatists and Continental socialists to whom scholars have typically ascribed Veblen's Darwinian roots. Additionally, that an extensive community continued to use Darwinian evolutionary theory to construct new models of scientific and social scientific analysis at the turn of the twentieth century, a period during which Darwinism was purportedly in decline, suggests that the "eclipse of Darwinism" narrative has been overstated in literature about Darwinism's intellectual arc.

  17. On the importance of controlling for effort in analysis of count survey data: Modeling population change from Christmas Bird Count data

    USGS Publications Warehouse

    Link, W.A.; Sauer, J.R.; Helbig, Andreas J.; Flade, Martin

    1999-01-01

    Count survey data are commonly used for estimating temporal and spatial patterns of population change. Since count surveys are not censuses, counts can be influenced by 'nuisance factors' related to the probability of detecting animals but unrelated to the actual population size. The effects of systematic changes in these factors can be confounded with patterns of population change. Thus, valid analysis of count survey data requires the identification of nuisance factors and flexible models for their effects. We illustrate using data from the Christmas Bird Count (CBC), a midwinter survey of bird populations in North America. CBC survey effort has substantially increased in recent years, suggesting that unadjusted counts may overstate population growth (or understate declines). We describe a flexible family of models for the effect of effort, that includes models in which increasing effort leads to diminishing returns in terms of the number of birds counted.

  18. Educating Jurors about Forensic Evidence: Using an Expert Witness and Judicial Instructions to Mitigate the Impact of Invalid Forensic Science Testimony.

    PubMed

    Eastwood, Joseph; Caldwell, Jiana

    2015-11-01

    Invalid expert witness testimony that overstated the precision and accuracy of forensic science procedures has been highlighted as a common factor in many wrongful conviction cases. This study assessed the ability of an opposing expert witness and judicial instructions to mitigate the impact of invalid forensic science testimony. Participants (N = 155) acted as mock jurors in a sexual assault trial that contained both invalid forensic testimony regarding hair comparison evidence, and countering testimony from either a defense expert witness or judicial instructions. Results showed that the defense expert witness was successful in educating jurors regarding limitations in the initial expert's conclusions, leading to a greater number of not-guilty verdicts. The judicial instructions were shown to have no impact on verdict decisions. These findings suggest that providing opposing expert witnesses may be an effective safeguard against invalid forensic testimony in criminal trials. © 2015 American Academy of Forensic Sciences.

  19. A Framework for Web Usage Mining in Electronic Government

    NASA Astrophysics Data System (ADS)

    Zhou, Ping; Le, Zhongjian

    Web usage mining has been a major component of management strategy to enhance organizational analysis and decision. The literature on Web usage mining that deals with strategies and technologies for effectively employing Web usage mining is quite vast. In recent years, E-government has received much attention from researchers and practitioners. Huge amounts of user access data are produced in Electronic government Web site everyday. The role of these data in the success of government management cannot be overstated because they affect government analysis, prediction, strategies, tactical, operational planning and control. Web usage miming in E-government has an important role to play in setting government objectives, discovering citizen behavior, and determining future courses of actions. Web usage mining in E-government has not received adequate attention from researchers or practitioners. We developed a framework to promote a better understanding of the importance of Web usage mining in E-government. Using the current literature, we developed the framework presented herein, in hopes that it would stimulate more interest in this important area.

  20. Overstating the evidence for lung cancer screening: the International Early Lung Cancer Action Program (I-ELCAP) study.

    PubMed

    Welch, H Gilbert; Woloshin, Steven; Schwartz, Lisa M; Gordis, Leon; Gøtzsche, Peter C; Harris, Russell; Kramer, Barnett S; Ransohoff, David F

    2007-11-26

    Last year, the New England Journal of Medicine ran a lead article reporting that patients with lung cancer had a 10-year survival approaching 90% if detected by screening spiral computed tomography. The publication garnered considerable media attention, and some felt that its findings provided a persuasive case for the immediate initiation of lung cancer screening. We strongly disagree. In this article, we highlight 4 reasons why the publication does not make a persuasive case for screening: the study had no control group, it lacked an unbiased outcome measure, it did not consider what is already known about this topic from previous studies, and it did not address the harms of screening. We conclude with 2 fundamental principles that physicians should remember when thinking about screening: (1) survival is always prolonged by early detection, even when deaths are not delayed nor any lives saved, and (2) randomized trials are the only way to reliably determine whether screening does more good than harm.

  1. “After my husband’s circumcision, I know that I am safe from diseases”: Women’s Attitudes and Risk Perceptions Towards Male Circumcision in Iringa, Tanzania

    PubMed Central

    Layer, Erica H.; Beckham, Sarah W.; Mgeni, Lilian; Shembilu, Catherine; Momburi, Romani B.; Kennedy, Caitlin E.

    2013-01-01

    While male circumcision reduces the risk of female-to-male HIV transmission and certain sexually transmitted infections (STIs), there is little evidence that circumcision provides women with direct protection against HIV. This study used qualitative methods to assess women’s perceptions of male circumcision in Iringa, Tanzania. Women in this study had strong preferences for circumcised men because of the low risk perception of HIV with circumcised men, social norms favoring circumcised men, and perceived increased sexual desirability of circumcised men. The health benefits of male circumcision were generally overstated; many respondents falsely believed that women are also directly protected against HIV and that the risk of all STIs is greatly reduced or eliminated in circumcised men. Efforts to engage women about the risks and limitations of male circumcision, in addition to the benefits, should be expanded so that women can accurately assess their risk of HIV or STIs during sexual intercourse with circumcised men. PMID:24009771

  2. Accounting for product substitution in the analysis of food taxes targeting obesity.

    PubMed

    Miao, Zhen; Beghin, John C; Jensen, Helen H

    2013-11-01

    We extend the existing literature on food taxes targeting obesity. We systematically incorporate the implicit substitution between added sugars and solid fats into a comprehensive food demand system and evaluate the effect of taxes on sugars and fats. The approach conditions how food and obesity taxes affect total calorie intake. The proposed methodology accounts for the ability of consumers to substitute leaner low-fat and low-sugar items for rich food items within the same food group. We calibrate this demand system approach using recent food intake data and existing estimates of price and income elasticities of demand. The demand system accounts for both the within-food group substitution and the substitution across these groups. Simulations of taxes on added sugars and solid fat show that the tax impact on consumption patterns is understated and the induced welfare loss is overstated when not allowing for the substitution possibilities within food groups. Copyright © 2012 John Wiley & Sons, Ltd.

  3. An explanation of resisted discoveries based on construal-level theory.

    PubMed

    Fang, Hui

    2015-02-01

    New discoveries and theories are crucial for the development of science, but they are often initially resisted by the scientific community. This paper analyses resistance to scientific discoveries that supplement previous research results or conclusions with new phenomena, such as long chains in macromolecules, Alfvén waves, parity nonconservation in weak interactions and quasicrystals. Construal-level theory is used to explain that the probability of new discoveries may be underestimated because of psychological distance. Thus, the insufficiently examined scope of an accepted theory may lead to overstating the suitable scope and underestimating the probability of its undiscovered counter-examples. Therefore, psychological activity can result in people instinctively resisting new discoveries. Direct evidence can help people judge the validity of a hypothesis with rational thinking. The effects of authorities and textbooks on the resistance to discoveries are also discussed. From the results of our analysis, suggestions are provided to reduce resistance to real discoveries, which will benefit the development of science.

  4. Bias in patient satisfaction surveys: a threat to measuring healthcare quality

    PubMed Central

    Dunsch, Felipe; Evans, David K; Macis, Mario; Wang, Qiao

    2018-01-01

    Patient satisfaction surveys are an increasingly common element of efforts to evaluate the quality of healthcare. Many patient satisfaction surveys in low/middle-income countries frame statements positively and invite patients to agree or disagree, so that positive responses may reflect either true satisfaction or bias induced by the positive framing. In an experiment with more than 2200 patients in Nigeria, we distinguish between actual satisfaction and survey biases. Patients randomly assigned to receive negatively framed statements expressed significantly lower levels of satisfaction (87%) than patients receiving the standard positively framed statements (95%—p<0.001). Depending on the question, the effect is as high as a 19 percentage point drop (p<0.001). Thus, high reported patient satisfaction likely overstates the quality of health services. Providers and policymakers wishing to gauge the quality of care will need to avoid framing that induces bias and to complement patient satisfaction measures with more objective measures of quality. PMID:29662696

  5. A comparison of soil moisture sensors for space flight applications

    NASA Technical Reports Server (NTRS)

    Norikane, J. H.; Prenger, J. J.; Rouzan-Wheeldon, D. T.; Levine, H. G.

    2005-01-01

    Plants will be an important part of future long-term space missions. Automated plant growth systems require accurate and reliable methods of monitoring soil moisture levels. There are a number of different methods to accomplish this task. This study evaluated sensors using the capacitance method (ECH2O), the heat-pulse method (TMAS), and tensiometers, compared to soil water loss measured gravimetrically in a side-by-side test. The experiment monitored evaporative losses from substrate compartments filled with 1- to 2-mm baked calcinated clay media. The ECH2O data correlated well with the gravimetric measurements, but over a limited range of soil moisture. The averaged TMAS sensor data overstated soil moisture content levels. The tensiometer data appeared to track evaporative losses in the 0.5- to 2.5-kPa range of matric potential that corresponds to the water content needed to grow plants. This small range is characteristic of large particle media, and thus high-resolution tensiometers are required to distinguish changing moisture contents in this range.

  6. Are Survey Respondents Lying about Their Support for Same-Sex Marriage? Lessons from a List Experiment

    PubMed Central

    Lax, Jeffrey R.; Phillips, Justin H.; Stollwerk, Alissa F.

    2016-01-01

    Public opinion polls consistently show that a growing majority of Americans support same-sex marriage. Critics, however, raise the possibility that these polls are plagued by social desirability bias, and thereby may overstate public support for gay and lesbian rights. We test this proposition using a list experiment embedded in the 2013 Cooperative Congressional Election Study. List experiments afford respondents an anonymity that allows them to provide more truthful answers to potentially sensitive survey items. Our experiment finds no evidence that social desirability is affecting overall survey results. If there is social desirability in polling on same-sex marriage, it pushes in both directions. Indeed, our efforts provide new evidence that a national opinion majority favors same-sex marriage. To evaluate the robustness of our findings, we analyze a second list experiment, this one focusing on the inclusion of sexual orientation in employment nondiscrimination laws. Again, we find no overall evidence of bias. PMID:27274575

  7. Personalising exercise recommendations for brain health: considerations and future directions.

    PubMed

    Barha, Cindy K; Galea, Liisa A; Nagamatsu, Lindsay S; Erickson, Kirk I; Liu-Ambrose, Teresa

    2017-04-01

    The societal value of strategies that delay the onset and progression of dementia cannot be overstated. Physical activity-unstructured and structured-is a promising, cost-effective strategy for the promotion of brain health. However, a large degree of variation exists in its efficacy. Therefore, to increase its utility as 'medication' for healthy cognitive ageing, it is imperative to identify key moderators and mediators of the positive effects of targeted exercise training on brain health. In this commentary, we focus on the type of targeted exercise training, the determinants of individual variation, including biological sex and genotypic factors, and the mechanisms by which exercise exerts its influence on the brain. We argue that a better understanding of these factors will allow for evidence-based, personalised, tailored exercise recommendations that go beyond the one-size-fits-all approach to successfully combat dementia. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  8. The costs and benefits of a cigarette ban.

    PubMed

    Doucet, Mathieu

    2017-06-01

    The death toll from tobacco is staggering: it might contribute to one billion premature deaths over the course of the 21st century. In 'The case for banning cigarettes', Kalle Grill and Kristin Voigt argue that the well-being and equality benefits of a complete ban on cigarettes more than justify the restrictions on autonomy that such a ban would impose. Their argument depends on two crucial simplifications: an assumption that the ban would be effective and the restriction of the analysis to a comparison with the status quo, rather than a broader range of policy options. I argue that despite the authors' claims, these two simplifications make it impossible for their argument to 'bring into focus the fundamental normative issues' surrounding a possible cigarette ban, since they dramatically overstate the benefits and obscure the most significant costs of such a ban. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  9. Incidence of real-world automotive parent and halogenated PAH in urban atmosphere.

    PubMed

    Gao, Pan-Pan; Zhao, Yi-Bo; Ni, Hong-Gang

    2018-06-01

    This study reports results from a tunnel experiment impact of real-world traffic-related particle and gas parent and halogenated polycyclic aromatic hydrocarbons (PAHs and HPAHs) on urban air. The traffic related emission characteristics and subsequent environmental behavior of these compounds were investigated. To understand the significance of real-world transport emissions to the urban air, traffic-related mass emissions of PAHs and HPAHs were estimated based on measured emission factors. According to our results, PAHs and HPAHs emissions via particulate phase were greater than those via gaseous phase; particles in 2.1-3.3 μm size fraction, have the major contribution to particulate PAHs and HPAHs emissions. Over all, contribution of traffic-related emission of PAHs (only ∼3% of the total PAHs emission in China) is an overstated source of PAHs pollution in China. Actually, exhaust pipe emission contributed much less than the total traffic-related emission of pollutants. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. Measuring suspended sediment: Chapter 10

    USGS Publications Warehouse

    Gray, J.R.; Landers, M.N.

    2013-01-01

    Suspended sediment in streams and rivers can be measured using traditional instruments and techniques and (or) surrogate technologies. The former, as described herein, consists primarily of both manually deployed isokinetic samplers and their deployment protocols developed by the Federal Interagency Sedimentation Project. They are used on all continents other than Antarctica. The reliability of the typically spatially rich but temporally sparse data produced by traditional means is supported by a broad base of scientific literature since 1940. However, the suspended sediment surrogate technologies described herein – based on hydroacoustic, nephelometric, laser, and pressure difference principles – tend to produce temporally rich but in some cases spatially sparse datasets. The value of temporally rich data in the accuracy of continuous sediment-discharge records is hard to overstate, in part because such data can often overcome the shortcomings of poor spatial coverage. Coupled with calibration data produced by traditional means, surrogate technologies show considerable promise toward providing the fluvial sediment data needed to increase and bring more consistency to sediment-discharge measurements worldwide.

  11. What U.S. data should be used to measure the price elasticity of demand for alcohol?

    PubMed

    Ruhm, Christopher J; Jones, Alison Snow; McGeary, Kerry Anne; Kerr, William C; Terza, Joseph V; Greenfield, Thomas K; Pandian, Ravi S

    2012-12-01

    This paper examines how estimates of the price elasticity of demand for beer vary with the choice of alcohol price series examined. Our most important finding is that the commonly used ACCRA price data are unlikely to reliably indicate alcohol demand elasticities-estimates obtained from this source vary drastically and unpredictably. As an alternative, researchers often use beer taxes to proxy for alcohol prices. While the estimated beer taxes elasticities are more stable, there are several problems with using taxes, including difficulties in accounting for cross-price effects. We believe that the most useful estimates reported in this paper are obtained using annual Uniform Product Code (UPC) "barcode" scanner data on grocery store alcohol prices. These estimates suggest relatively low demand elasticity, probably around -0.3, with evidence that the elasticities are considerably overstated in models that control for beer but not wine or spirits prices. Copyright © 2012 Elsevier B.V. All rights reserved.

  12. What Skills Can Buy: Transmission of advantage through cognitive and noncognitive skills

    PubMed Central

    Doren, Catherine; Grodsky, Eric

    2017-01-01

    Parental income and wealth contribute to children’s success but are at least partly endogenous to parents’ cognitive and noncognitive skills. We estimate the degree to which mothers’ skills measured in early adulthood confound the relationship between their economic resources and their children’s postsecondary education outcomes. Analyses of NLSY79 suggest that maternal cognitive and noncognitive skills attenuate half of parental income’s association with child baccalaureate college attendance, a fifth of its association with elite college attendance, and a quarter of its association with bachelor’s degree completion. Maternal skills likewise attenuate a third of parental wealth’s association with children’s baccalaureate college attendance, half of its association with elite college attendance, and a fifth of its association with bachelor’s degree completion. Observational studies of the relationship between parents’ economic resources and children’s postsecondary attainments that fail to account for parental skills risk seriously overstating the benefits of parental income and wealth. PMID:28337046

  13. Base rate of performance invalidity among non-clinical undergraduate research participants.

    PubMed

    Silk-Eglit, Graham M; Stenclik, Jessica H; Gavett, Brandon E; Adams, Jason W; Lynch, Julie K; Mccaffrey, Robert J

    2014-08-01

    Neuropsychological research frequently uses non-clinical undergraduate participants to evaluate neuropsychological tests. However, a recent study by An and colleagues (2012, Archives of Clinical Neuropsychology, 27, 849-857) called into question that the extent to which the interpretation of these participants' performance on neuropsychological tests is valid. This study found that in a sample of 36 participants, 55.6% exhibited performance invalidity at an initial session and 30.8% exhibited performance invalidity at a follow-up session. The current study attempted to replicate these findings in a larger, more representative sample using a more rigorous methodology. Archival data from 133 non-clinical undergraduate research participants were analyzed. Participants were classified as performance invalid if they failed any one PVT. In the current sample, only 2.26% of participants exhibited performance invalidity. Thus, concerns regarding insufficient effort and performance invalidity when using undergraduate research participants appear to be overstated. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. The Vision for Space Exploration

    NASA Technical Reports Server (NTRS)

    2004-01-01

    With last year's budget, NASA released a new Strategic Plan outlining a new approach to space exploration using a 'building block' strategy to explore scientifically valuable destinations across our solar system. At the same time that we released the Strategic Plan, our Nation and the NASA family also suffered the loss of the seven brave astronauts aboard the Space Shuttle Columbia. The report of the Columbia Accident Investigation Board emphasized the need for a clearer direction from which to drive NASA's human exploration agenda. On January 14, 2004, the President articulated a new vision for space exploration. You hold in your hands a new, bolder framework for exploring our solar system that builds upon the policy that was announced by the President after months of careful deliberations within the Administration. This plan does not undertake exploration merely for the sake of adventure, however exciting that may be, but seeks answers to profound scientific and philosophical questions, responds to recent discoveries, will put in place revolutionary technologies and capabilities for the future, and will genuinely inspire our Nation, the world, and the next generation. Our aim is to explore in a sustainable, affordable, and flexible manner. We believe the principles and roadmap set down in this document will stand the test of time. Its details will be subject to revision and expansion as new discoveries are made, new technologies are applied, and new challenges are met and overcome. This plan is guided by the Administration's new space exploration policy, 'A Renewed Spirit of Discovery: The President's Vision for U.S. Space Exploration,' a copy of which is provided on the following pages. NASA is releasing this plan simultaneously with NASA's FY 2005 Budget Justification. This plan is fiscally responsible, consistent with the Administration s goal of cutting the budget deficit in half within the next five years. I cannot overstate how much NASA will change in the coming years as this plan is implemented. I also cannot overstate how profound the rewards will be on this new course. With the support of Congress, the science community, the NASA civil and contractor workforce, and most importantly, the American public, we will embark on this very exciting future. When Christopher Columbus made his voyages across the Atlantic in the 15th and 16th centuries, his ships carried the inscription 'Following the light of the sun, we left the Old World.' I look forward to joining you as we follow the light of the planets and the stars into the new worlds of the 21st century.

  15. Modelling of Resonantly Forced Density Waves in Dense Planetary Rings

    NASA Astrophysics Data System (ADS)

    Lehmann, M.; Schmidt, J.; Salo, H.

    2014-04-01

    Density wave theory, originally proposed to explain the spiral structure of galactic disks, has been applied to explain parts of the complex sub-structure in Saturn's rings, such as the wavetrains excited at the inner Lindblad resonances (ILR) of various satellites. The linear theory for the excitation and damping of density waves in Saturn's rings is fairly well developed (e.g. Goldreich & Tremaine [1979]; Shu [1984]). However, it fails to describe certain aspects of the observed waves. The non-applicability of the linear theory is already indicated by the "cusplike" shape of many of the observed wave profiles. This is a typical nonlinear feature which is also present in overstability wavetrains (Schmidt & Salo [2003]; Latter & Ogilvie [2010]). In particular, it turns out that the detailed damping mechanism, as well as the role of different nonlinear effects on the propagation of density waves remain intransparent. First attemps are being made to investigate the excitation and propagation of nonlinear density waves within a hydrodynamical formalism, which is also the natural formalism for describing linear density waves. A simple weakly nonlinear model, derived from a multiple-scale expansion of the hydrodynamic equations, is presented. This model describes the damping of "free" spiral density waves in a vertically integrated fluid disk with density dependent transport coefficients, where the effects of the hydrodynamic nonlinearities are included. The model predicts that density waves are linearly unstable in a ring region where the conditions for viscous overstability are met, which translates to a steep dependence of the shear viscosity with respect to the disk's surface density. The possibility that this dependence could lead to a growth of density waves with increasing distance from the resonance, was already mentioned in Goldreich & Tremaine [1978]. Sufficiently far away from the ILR, the surface density perturbation caused by the wave, is predicted to saturate to a constant value due to the effects of nonlinear viscous damping. A qualitatively similar behaviour has also been predicted for the damping of nonlinear density waves, as described within a streamline formalism (Borderies, Goldreich & Tremaine [1985]). The damping lengths which follow from the weakly nonlinear model depend more or less strongly on a set of different input parameters, such as the viscosity and the surface density of the unperturbed ring state. Further, they depend on the wave's amplitude at resonance. For a real wave, which has been excited by an external satellite, this amplitude can be deduced from the magnitude of the satellite's forcing potential. Appart from that, hydrodynamical simulations are being developed to study the nonlinear damping of resonantly forced density waves.

  16. Bringing a probiotic-containing functional food to the market: microbiological, product, regulatory and labeling issues.

    PubMed

    Sanders, M E; Huis in't Veld, J

    1999-01-01

    Properly formulated probiotic-containing foods offer consumers a low risk, low cost dietary component that has the potential to promote health in a variety of ways. Several such products are available commercially, although markets in Japan and Europe are more developed than in the USA. Once healthful attributes of a probiotic product have been identified, there remain microbiological, product, regulatory and labeling issues to be addressed prior to marketing. Microbiological and product issues include safety, effective scale-up for manufacturing, definition of probiotic activity, probiotic stability in the product over the course of product manufacture, shelf-life and consumption, definition of effective dose and target population(s), and development of quality assurance approaches. Examples of probiotic-containing foods are given. Regulatory and labeling issues are complicated because they differ for each country, but are likewise critical because they provide the means for communication of the product benefits to the consumer. The regulatory climate worldwide appears to be one of caution about overstating the benefits of such products but at the same time not preventing corporate commitment to marketing.

  17. The impact of climate change on coastal ecosystems: chapter 6

    USGS Publications Warehouse

    Burkett, Virginia; Woodroffe, Colin D.; Nicholls, Robert J.; Forbes, Donald L.

    2014-01-01

    In this chapter we stress two important features of coasts and coastal ecosystems. First, these are dynamic systems which continually undergo adjustments, especially through erosion and re-deposition, in response to a range of processes. Many coastal ecosystems adjust naturally at a range of time scales and their potential for response is examined partly by reconstructing how such systems have coped with natural changes of climate and sea level in the geological past. Second, coasts have changed profoundly through the 20th Century due to the impacts of human development (such as urbanisation, port and industrial expansion, shore protection, and the draining and conversion of coastal wetlands), with these development-related drivers closely linked to a growing global population and economy. It remains a challenge to isolate the impacts of climate change and sea-level rise from either the natural trajectory of shoreline change, or the accelerated pathway resulting from other human-related stressors. There exists a danger of overstating the importance of climate change, or overlooking significant interactions of climate change with other drivers.

  18. Study of effects of radio-wave frequency radiation emitted from cellular telephones on embryonic development of danio rerio

    NASA Astrophysics Data System (ADS)

    Vagula, Mary; Harkless, Ryan

    2013-05-01

    Radio wave frequency (RF) radiation emitted from cellular telephones has become increasingly ubiquitous as a result of the popularity of these phones. With the increasing and unavoidable exposure to RF radiation a reality, it is imperative that the effects of such radiation on living tissue be well understood. In particular, it is critical to understand any effects that RF radiation may have as a carcinogen and on embryonic development, as pregnant women are not exempt from such exposure. As a model organism, zebrafish (Danio rerio) have been studied extensively, and their value in studies of gene expression cannot be overstated. This study observed the effects of RF radiation on the embryonic development of zebrafish. The expression of two genes, shha and hoxb9a, that are key to the early development of the fish was examined. Both genes have homologs in humans as well as in other model organisms. Preliminary results suggest that exposure to cell phone radiation might have an effect on the expression of shha in zebrafish embryos, causing under expression. More trials are necessary to validate these results.

  19. A randomized controlled trial of low carbohydrate and low fat/high fiber diets for weight loss.

    PubMed Central

    Baron, J A; Schori, A; Crow, B; Carter, R; Mann, J I

    1986-01-01

    Among 135 overweight subjects, we conducted a three-month randomized controlled trial of two sets of dietary advice, each providing approximately 1,000 calories per day but differing in fiber, carbohydrate, and fat content. Information on weight and eating habits, as well as measures of lipoprotein and glucose metabolism were obtained at entry and one and three months later. We found that dieters given low carbohydrate/low fiber dietary advice tended to lose more weight than those given a higher carbohydrate/higher fiber regimen (5.0 vs 3.7 kg on average at three months). This pattern was particularly marked among women, and among participants who were under age 40 or of lower social class. There were no differences between the diet groups in the proportion complaining of hunger but, in general, members of the low carbohydrate group complained of more problems in dieting. There were only minor differences in the serum lipoprotein patterns during the diet period. In view of these results, we believe previous claims of the benefits of fiber for weight loss may have been overstated. PMID:3021006

  20. The characters of Palaeozoic jawed vertebrates

    PubMed Central

    Brazeau, Martin D; Friedman, Matt

    2014-01-01

    Newly discovered fossils from the Silurian and Devonian periods are beginning to challenge embedded perceptions about the origin and early diversification of jawed vertebrates (gnathostomes). Nevertheless, an explicit cladistic framework for the relationships of these fossils relative to the principal crown lineages of the jawed vertebrates (osteichthyans: bony fishes and tetrapods; chondrichthyans: sharks, batoids, and chimaeras) remains elusive. We critically review the systematics and character distributions of early gnathostomes and provide a clearly stated hierarchy of synapomorphies covering the jaw-bearing stem gnathostomes and osteichthyan and chondrichthyan stem groups. We show that character lists, designed to support the monophyly of putative groups, tend to overstate their strength and lack cladistic corroboration. By contrast, synapomorphic hierarchies are more open to refutation and must explicitly confront conflicting evidence. Our proposed synapomorphy scheme is used to evaluate the status of the problematic fossil groups Acanthodii and Placodermi, and suggest profitable avenues for future research. We interpret placoderms as a paraphyletic array of stem-group gnathostomes, and suggest what we regard as two equally plausible placements of acanthodians: exclusively on the chondrichthyan stem, or distributed on both the chondrichthyan and osteichthyan stems. PMID:25750460

  1. Does Displaying the Class Results Affect Student Discussion during Peer Instruction?

    PubMed Central

    Strauss, Eric A.; Downey, Nicholas; Galbraith, Anne; Jeanne, Robert; Cooper, Scott

    2010-01-01

    The use of personal response systems, or clickers, is increasingly common in college classrooms. Although clickers can increase student engagement and discussion, their benefits also can be overstated. A common practice is to ask the class a question, display the responses, allow the students to discuss the question, and then collect the responses a second time. In an introductory biology course, we asked whether showing students the class responses to a question biased their second response. Some sections of the course displayed a bar graph of the student responses and others served as a control group in which discussion occurred without seeing the most common answer chosen by the class. If students saw the bar graph, they were 30% more likely to switch from a less common to the most common response. This trend was more pronounced in true/false questions (38%) than multiple-choice questions (28%). These results suggest that observing the most common response can bias a student's second vote on a question and may be misinterpreted as an increase in performance due to student discussion alone. PMID:20516358

  2. When do latent class models overstate accuracy for diagnostic and other classifiers in the absence of a gold standard?

    PubMed

    Spencer, Bruce D

    2012-06-01

    Latent class models are increasingly used to assess the accuracy of medical diagnostic tests and other classifications when no gold standard is available and the true state is unknown. When the latent class is treated as the true class, the latent class models provide measures of components of accuracy including specificity and sensitivity and their complements, type I and type II error rates. The error rates according to the latent class model differ from the true error rates, however, and empirical comparisons with a gold standard suggest the true error rates often are larger. We investigate conditions under which the true type I and type II error rates are larger than those provided by the latent class models. Results from Uebersax (1988, Psychological Bulletin 104, 405-416) are extended to accommodate random effects and covariates affecting the responses. The results are important for interpreting the results of latent class analyses. An error decomposition is presented that incorporates an error component from invalidity of the latent class model. © 2011, The International Biometric Society.

  3. Organ donation and transplantation in Canada: insights from the Canadian Organ Replacement Register.

    PubMed

    Kim, Sang Joseph; Fenton, Stanley Sa; Kappel, Joanne; Moist, Louise M; Klarenbach, Scott W; Samuel, Susan M; Singer, Lianne G; Kim, Daniel H; Young, Kimberly; Webster, Greg; Wu, Juliana; Ivis, Frank; de Sa, Eric; Gill, John S

    2014-01-01

    To provide an overview of the transplant component of the Canadian Organ Replacement Register (CORR). CORR is the national registry of organ failure in Canada. It has existed in some form since 1972 and currently houses data on patients with end-stage renal disease and solid organ transplants (kidney and/or non-kidney). The transplant component of CORR receives data on a voluntary basis from individual transplant centres and organ procurement organizations across the country. Coverage for transplant procedures is comprehensive and complete. Long-term outcomes are tracked based on follow-up reports from participating transplant centres. The longitudinal nature of CORR provides an opportunity to observe the trajectory of a patient's journey with organ failure over their life span. Research studies conducted using CORR data inform both practitioners and health policy makers alike. The importance of registry data in monitoring and improving care for Canadian transplant candidates/recipients cannot be over-stated. This paper provides an overview of the transplant data in CORR including its history, data considerations, recent findings, new initiatives, and future directions.

  4. [A correct understanding of preservatives in eye drops].

    PubMed

    Liu, Zuguo; Huang, Caihong

    2015-09-01

    Eye drops are the most commonly used preparations in ophthalmology. Preservatives are usually added in order to protect eye drops against pathogenic organisms and increase the solubility of the drugs in multi-dose containers. Ophthalmologists have paid a lot of attention to the preservatives in eye drops because they remain one of the main reasons for ocular surface damage, and even may lead to serious visual impairment in patients with inappropriate use of eye drops. However, it should be noted that the dangers of preservatives become overstated nowadays. It is necessary to completely evaluate the effects of preservatives in ophthalmic preparations, so that ophthalmologists can guide patients to correctly select eye drops containing preservatives and avoid dangerous side effects, according to their eye disease situation, state of tear function and ocular surface changes, cultural background and financial income, cost and benefit and convenience of the use of drugs, and other factors. The direction of the future development in this field is to establish the clinical guideline for use of eye drops containing preservatives, carry out continuing education courses on preservatives and develop ideal preservatives.

  5. Phi in physiology, psychology and biomechanics: The golden ratio between myth and science.

    PubMed

    Iosa, Marco; Morone, Giovanni; Paolucci, Stefano

    2018-03-01

    In recent years, there has been a renewed interest in the use of the so-called golden ratio (Phi, ϕ), an irrational number with fractal properties, used in artworks since V century BC. and now for modelling complex biological structures and functions. This number, in fact, recursively pops-up in human history, from Ancient Greeks to Renaissance, and to contemporary scientific studies. Nevertheless, recent scientific results often fall between two extremes: those of a priori sceptic researchers accusing the artificial emergence of ϕ in many studies, and those of researchers that find a mystic meaning in the presence of ϕ in human physiology. This review moves between these two extremes to provide a scientifically based discussion about the possible presence of Phi in human physiology, psychology, and biomechanics of heart and locomotion. We provide scientific evidence, analysing reasons for the presence of Phi, reporting the weakness of some studies overstating the potential meaning of this number, and reporting the reasons for which it could be actually found in some biological structures and functions. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Operative Treatment of Traumatic Hallux Valgus in Elite Athletes.

    PubMed

    Covell, D Jeff; Lareau, Craig R; Anderson, Robert B

    2017-06-01

    Traumatic hallux valgus is an increasingly common injury in the athletic population and represents a unique variant of turf toe. Failure to appropriately recognize and treat these injuries can lead to continued pain, decreased performance, progressive deformities, and ultimately degeneration of the hallux metatarsophalangeal joint. Limited literature currently exists to assist in the diagnosis, management, and operative treatment. Nineteen patients were reviewed in this series, including 12 National Football League, 6 college, and 1 high school player who was a college prospect. The average age for all patients at the time of surgery was 24.4 years (range, 19-33 years). Return to play and complications were evaluated. Overall, good operative results were obtained, with 74% of patients returning to their preinjury level of play at an average recovery time of 3.4 months. Traumatic hallux valgus is an increasingly common injury in the athletic population and represents a unique variant of turf toe. The impact of this injury cannot be overstated, as one-quarter of players were unable to return to play. Level IV, case series.

  7. Who is buying bioethics research?

    PubMed

    Sharp, Richard R; Scott, Angela L; Landy, David C; Kicklighter, Laura A

    2008-08-01

    Growing ties to private industry have prompted many to question the impartiality of academic bioethicists who receive financial support from for-profit corporations in exchange for ethics-related services and research. To the extent that corporate sponsors may view bioethics as little more than a way to strengthen public relations or avoid potential controversy, close ties to industry may pose serious threats to professional independence. New sources of support from private industry may also divert bioethicists from pursuing topics of greater social importance, such as the needs of medically underserved communities. To inform ongoing debates about the financing of bioethics and its transparency to those concerned about potential sources of bias, we examined funding disclosures appearing in original research reports in major bioethics journals. Reviewing research published over a 15-year period, we found little evidence that for-profit corporations are influencing bioethics research directly. Instead, we found evidence that a great number of organizations, both public and private, support bioethics research. These findings suggest that worries about the cooption of bioethics research by a few interested stakeholders are greatly overstated and undersupported by available data.

  8. Forum: The challenge of global change

    NASA Astrophysics Data System (ADS)

    Roederer, Juan G.

    1990-09-01

    How can we sustain a public sense of the common danger of global change while remaining honest in view of the realities of scientific uncertainty? How can we nurture this sense of common danger without making statements based on half-baked ideas, statistically unreliable results, or oversimplified models? How can we strike a balance between the need to overstate a case to attract the attention of the media and the obligation to adhere strictly to the ethos of science?The task of achieving a scientific understanding of the inner workings of the terrestrial environment is one of the most difficult and ambitious endeavors of humankind. It is full of traps, temptations and deceptions for the participating scientists. We are dealing with a horrendously complex, strongly interactive, highly non-linear system. Lessons learned from disciplines such as plasma physics and solid state physics which have been dealing with complex non-linear systems for decades, are not very encouraging. The first thing one learns is that there are intrinsic, physical limits to the quantitative predictability of a complex system that have nothing to do with the particular techniques employed to model it.

  9. Straight ahead running of a nonlinear car and driver model - new nonlinear behaviours highlighted

    NASA Astrophysics Data System (ADS)

    Della Rossa, Fabio; Mastinu, Giampiero

    2018-05-01

    The paper deals with the bifurcation analysis of a validated simple model describing a vehicle+driver running straight ahead. The mechanical model of the car has two degrees of freedom and the related equations of motion contain the nonlinear tyre characteristics. The driver is described by a very simple model. Bifurcation analysis is adopted for characterising straight ahead motion at different speeds for different drivers. A nonlinear sensitivity analysis is performed as a function of the driver's parameters and forward vehicle speed. A wealth of unreferenced bifurcations is discovered both for the understeering (UN) and for the oversteering (OV) vehicle. For the UN vehicle, a supercritical Hopf bifurcation may occur as the forward speed is increased. Also tangent (fold) bifurcations (saddle-node bifurcation of limit cycles) occur as the speed (or disturbance) is further increased. For the OV vehicle, a subcritical Hopf bifurcation occurs as the speed reaches a critical value. The preview distance (a driver's control parameter) plays a fundamental role in straight ahead driving. Either too short or too long preview distances are negative for straight ahead running.

  10. Compressible Analysis of Bénard Convection of Magneto Rotatory Couple-Stress Fluid

    NASA Astrophysics Data System (ADS)

    Mehta, C. B.; Singh, M.

    2018-02-01

    Thermal Instability (Benard's Convection) in the presence of uniform rotation and uniform magnetic field (separately) is studied. Using the linearized stability theory and normal mode analyses the dispersion relation is obtained in each case. In the case of rotatory Benard's stationary convection compressibility and rotation postpone the onset of convection whereas the couple-stress have duel character onset of convection depending on rotation parameter. While in the absence of rotation couple-stress always postpones the onset of convection. On the other hand, magnetic field on thermal instability problem on couple-stress fluid for stationary convection couple-stress parameter and magnetic field postpones the onset of convection. The effect of compressibility also postpones the onset of convection in both cases as rotation and magnetic field. Graphs have been plotted by giving numerical values to the parameters to depict the stationary characteristics. Further, the magnetic field and rotation are found to introduce oscillatory modes which were non-existent in their absence and then the principle of exchange of stability is valid. The sufficient conditions for non-existence of overstability are also obtained.

  11. Gender Differences in Neurodevelopment and Epigenetics

    PubMed Central

    Chung, Wilson C.J.; Auger, Anthony P.

    2013-01-01

    Summary The concept that the brain differs in make-up between males and females is not new. For example, it is well-established that anatomists in the nineteenth century found sex differences in human brain weight. The importance of sex differences in the organization of the brain cannot be overstated as they may directly affect cognitive functions, such as verbal skills and visio-spatial tasks in a sex-dependent fashion. Moreover, the incidence of neurological and psychiatric diseases is also highly dependent on sex. These clinical observations reiterate the importance that gender must be taken into account as a relevant possible contributing factor in order to understand the pathogenesis of neurological and psychiatric disorders. Gender-dependent differentiation of the brain has been detected at every levels of organization: morphological, neurochemical, and functional, and have been shown to be primarily controlled by sex differences in gonadal steroid hormone levels during perinatal development. In this review, we discuss how the gonadal steroid hormone testosterone and its metabolites, affect downstream signaling cascades, including gonadal steroid receptor activation, and epigenetic events in order to differentiate the brain in a gender-dependent fashion. PMID:23503727

  12. Recessions and Health: The Impact of Economic Trends on Air Pollution in California

    PubMed Central

    2012-01-01

    Objectives. I explored the hypothesis that economic activity has a significant impact on exposure to air pollution and ultimately human health. Methods. I used county-level employment statistics in California (1980–2000), along with major regulatory periods and other controlling factors, to estimate local concentrations of the coefficient of haze, carbon monoxide, and nitrogen dioxide using a mixed regression model approach. Results. The model explained between 33% and 48% of the variability in air pollution levels as estimated by the overall R2 values. The relationship between employment measures and air pollution was statistically significant, suggesting that air quality improves during economic downturns. Additionally, major air quality regulations played a significant role in reducing air pollution levels over the study period. Conclusions. This study provides important evidence of a role for the economy in understanding human exposure to environmental pollution. The evidence further suggests that the impact of environmental regulations are likely to be overstated when they occur during recessionary periods, and understated when they play out during periods of economic growth. PMID:22897522

  13. Analysis of overdispersed count data: application to the Human Papillomavirus Infection in Men (HIM) Study.

    PubMed

    Lee, J-H; Han, G; Fulp, W J; Giuliano, A R

    2012-06-01

    The Poisson model can be applied to the count of events occurring within a specific time period. The main feature of the Poisson model is the assumption that the mean and variance of the count data are equal. However, this equal mean-variance relationship rarely occurs in observational data. In most cases, the observed variance is larger than the assumed variance, which is called overdispersion. Further, when the observed data involve excessive zero counts, the problem of overdispersion results in underestimating the variance of the estimated parameter, and thus produces a misleading conclusion. We illustrated the use of four models for overdispersed count data that may be attributed to excessive zeros. These are Poisson, negative binomial, zero-inflated Poisson and zero-inflated negative binomial models. The example data in this article deal with the number of incidents involving human papillomavirus infection. The four models resulted in differing statistical inferences. The Poisson model, which is widely used in epidemiology research, underestimated the standard errors and overstated the significance of some covariates.

  14. Marketplace Plans Provide Risk Protection, But Actuarial Values Overstate Realized Coverage For Most Enrollees.

    PubMed

    Polyakova, Maria; Hua, Lynn Mei; Bundorf, M Kate

    2017-12-01

    The Affordable Care Act (ACA) has increased the number of Americans with health insurance. Yet many policy makers and consumers have questioned the value of Marketplace plan coverage because of the generally high levels of cost sharing. We simulated out-of-pocket spending for bronze, silver, or gold Marketplace plans (those having actuarial values of 60 percent, 70 percent, and 80 percent, respectively). We found that for the vast majority of consumers, the proportion of covered spending paid by the plans is likely to be far less than their actuarial values, the metric commonly used to convey plan generosity. Indeed, only when annual health care spending exceeds $16,500 for bronze plans, $19,500 for silver plans, and $21,500 for gold plans do plans in these metal tiers cover the proportion of costs matching their actuarial values. While Marketplace plans substantially reduce consumers' exposure to financial risk relative to being uninsured, the use of actuarial values to communicate plan generosity is likely to be misleading to consumers.

  15. Ranking Bias in Association Studies

    PubMed Central

    Jeffries, Neal O.

    2009-01-01

    Background It is widely appreciated that genomewide association studies often yield overestimates of the association of a marker with disease when attention focuses upon the marker showing the strongest relationship. For example, in a case-control setting the largest (in absolute value) estimated odds ratio has been found to typically overstate the association as measured in a second, independent set of data. The most common reason given for this observation is that the choice of the most extreme test statistic is often conditional upon first observing a significant p value associated with the marker. A second, less appreciated reason is described here. Under common circumstances it is the multiple testing of many markers and subsequent focus upon those with most extreme test statistics (i.e. highly ranked results) that leads to bias in the estimated effect sizes. Conclusions This bias, termed ranking bias, is separate from that arising from conditioning on a significant p value and may often be a more important factor in generating bias. An analytic description of this bias, simulations demonstrating its extent, and identification of some factors leading to its exacerbation are presented. PMID:19172085

  16. A comment on “temporal variation in survival and recovery rates of lesser scaup”

    USGS Publications Warehouse

    Lindberg, Mark S.; Boomer, G. Scott; Schmutz, Joel A.; Walker, Johann A.

    2017-01-01

    Concerns about declines in the abundance of lesser scaup (Aythya affinis) have promoted a number of analyses to understand reasons for this decline. Unfortunately, most of these analyses, including that of Arnold et al. (2016 Journal of Wildlife Management 80: 850–861), are based on observational studies leading to weak inference. Although we commend the efforts of Arnold et al. (2016 Journal of Wildlife Management 80: 850–861), we think their conclusions are over-stated given their retrospective analysis. Further, we note a number of inconsistencies in their reasoning and offer alternative conclusions that can be drawn from their analysis. Given the uncertainty still surrounding management of lesser scaup, we do not believe it is prudent to abandon or greatly modify adaptive management approaches designed specifically to make optimal decisions in the face of uncertainty. The current learning-based and recursive approach to management appears to be providing adequate guidance for harvest without punctuated changes to harvest levels, as Arnold et al. (2016 Journal of Wildlife Management 80: 850–861) recommend.

  17. New DEMs may stimulate significant advancements in remote sensing of soil moisture

    NASA Astrophysics Data System (ADS)

    Nolan, Matt; Fatland, Dennis R.

    From Napoleon's defeat at Waterloo to increasing corn yields in Kansas to greenhouse gas flux in the Arctic, the importance of soil moisture is endemic to world affairs and merits the considerable attention it receives from the scientific community. This importance can hardly be overstated, though it often goes unstated.Soil moisture is one of the key variables in a variety of broad areas critical to the conduct of societies' economic and political affairs and their well-being; these include the health of agricultural crops, global climate dynamics, military trafficability planning, and hazards such as flooding and forest fires. Unfortunately the in situ measurement of the spatial distribution of soil moisture on a watershed-scale is practically impossible. And despite decades of international effort, a satellite remote sensing technique that can reliably measure soil moisture with a spatial resolution of meters has not yet been identified or implemented. Due to the lack of suitable measurement techniques and, until recently digital elevation models (DEMs), our ability to understand and predict soil moisture dynamics through modeling has largely remained crippled from birth [Grayson and Bloschl, 200l].

  18. Cross-cultural differences and similarities underlying other-race effects for facial identity and expression.

    PubMed

    Yan, Xiaoqian; Andrews, Timothy J; Jenkins, Rob; Young, Andrew W

    2016-01-01

    Perceptual advantages for own-race compared to other-race faces have been demonstrated for the recognition of facial identity and expression. However, these effects have not been investigated in the same study with measures that can determine the extent of cross-cultural agreement as well as differences. To address this issue, we used a photo sorting task in which Chinese and Caucasian participants were asked to sort photographs of Chinese or Caucasian faces by identity or by expression. This paradigm matched the task demands of identity and expression recognition and avoided constrained forced-choice or verbal labelling requirements. Other-race effects of comparable magnitude were found across the identity and expression tasks. Caucasian participants made more confusion errors for the identities and expressions of Chinese than Caucasian faces, while Chinese participants made more confusion errors for the identities and expressions of Caucasian than Chinese faces. However, analyses of the patterns of responses across groups of participants revealed a considerable amount of underlying cross-cultural agreement. These findings suggest that widely repeated claims that members of other cultures "all look the same" overstate the cultural differences.

  19. Utility of Teacher-Report Assessments of Autistic Severity in Japanese School Children

    PubMed Central

    Moriwaki, Aiko; Inada, Naoko

    2013-01-01

    Recent studies suggest that many children with milder autism spectrum disorder (ASD) are undiagnosed, untreated, and being educated in mainstream classes without support and that school teachers might be the best persons to identify a child's social deviance. At present, only a few screening measures using teacher ratings of ASD have been validated. The aim of this study was to examine the utility of teacher ratings on the Social Responsiveness Scale (SRS), a quantitative measure of ASD. We recruited 130 participants aged 4 to 17 years from local schools or local pediatric outpatient clinics specializing in neurodevelopmental disorders that included 70 children with ASD. We found that the teacher-report SRS can be reliably and validly applied to children as a screening tool or for other research purposes, and it also has cross-cultural comparability. Although parent-teacher agreement was satisfactory overall, a discrepancy existed for children with ASD, especially for girls with ASD. To improve sensitivity in children at higher risk, especially girls, we cannot overstate the importance of using standardized norms specific to gender, informant, and culture. PMID:24392224

  20. Science or propaganda?an examination of rind, tromovitch and bauserman (1998).

    PubMed

    Dallam, S J

    2000-01-01

    An article, “A Meta-analytic Examination of Assumed Properties of Child Sexual Abuse Using College Samples,” published in the July 1998 edition of the Psychological Bulletin resulted in an unprecedented amount of media attention and became the first scientific article to be formally denounced by the United States House of Representatives. The study's authors analyzed the findings of 59 earlier studies on child sexual abuse (CSA) and concluded that mental health researchers have greatly overstated CSA's harmful potential. They recommended that a willing encounter with positive reactions would no longer be considered to be sexual abuse; instead, it would simply be labeled adult-child sex. The study's conclusions and recommendations spawned a debate in both the popular and scholarly press. A number of commentators suggested that the study is pedophile propaganda masquerading as science. Others claimed that the authors are victims of a moralistic witch-hunt and that scientific freedom is being threatened. After a careful examination of the evidence, it is concluded that Rind et al. can best be described as an advocacy article that inappropriately uses science in an attempt to legitimize its findings.

  1. A retrospective review of the carcinogenicity of refractory ceramic fiber in two chronic fischer 344 rat inhalation studies: an assessment of the MTD and implications for risk assessment.

    PubMed

    Mast, R W; Yu, C P; Oberdörster, G; McConnell, E E; Utell, M J

    2000-12-01

    The purpose of this article is to review previous chronic inhalation studies in rats with refractory ceramic fiber (RCF), the mathematical modeling efforts to describe the deposition, clearance, and retention of RCF fiber in the rat and human, and the concept of "overload," and to assess the possibility that the maximum tolerated dose (MTD) was exceeded. Lastly, based on recent biopersistence and pulmonary clearance studies of several investigators with a particulate-free RCF, we examine the potential impact on the chronic RCF rat bioassay of coexposure to both RCF particulate and RCF fibers. The review concludes, inter alia, that RCF particulate coexposure probably had a major impact on the observed chronic adverse effects, that the MTD was probably exceeded at the highest exposure concentration of 30 mg/m(3) in the rat bioassay, and that inclusion of the highest dose in the risk assessment process may overstate human health risk if a linear rather than nonlinear model is used.

  2. Endoscope field of view measurement.

    PubMed

    Wang, Quanzeng; Khanicheh, Azadeh; Leiner, Dennis; Shafer, David; Zobel, Jurgen

    2017-03-01

    The current International Organization for Standardization (ISO) standard (ISO 8600-3: 1997 including Amendment 1: 2003) for determining endoscope field of view (FOV) does not accurately characterize some novel endoscopic technologies such as endoscopes with a close focus distance and capsule endoscopes. We evaluated the endoscope FOV measurement method (the FOV WS method) in the current ISO 8600-3 standard and proposed a new method (the FOV EP method). We compared the two methods by measuring the FOV of 18 models of endoscopes (one device for each model) from seven key international manufacturers. We also estimated the device to device variation of two models of colonoscopes by measuring several hundreds of devices. Our results showed that the FOV EP method was more accurate than the FOV WS method, and could be used for all endoscopes. We also found that the labelled FOV values of many commercial endoscopes are significantly overstated. Our study can help endoscope users understand endoscope FOV and identify a proper method for FOV measurement. This paper can be used as a reference to revise the current endoscope FOV measurement standard.

  3. Endoscope field of view measurement

    PubMed Central

    Wang, Quanzeng; Khanicheh, Azadeh; Leiner, Dennis; Shafer, David; Zobel, Jurgen

    2017-01-01

    The current International Organization for Standardization (ISO) standard (ISO 8600-3: 1997 including Amendment 1: 2003) for determining endoscope field of view (FOV) does not accurately characterize some novel endoscopic technologies such as endoscopes with a close focus distance and capsule endoscopes. We evaluated the endoscope FOV measurement method (the FOVWS method) in the current ISO 8600-3 standard and proposed a new method (the FOVEP method). We compared the two methods by measuring the FOV of 18 models of endoscopes (one device for each model) from seven key international manufacturers. We also estimated the device to device variation of two models of colonoscopes by measuring several hundreds of devices. Our results showed that the FOVEP method was more accurate than the FOVWS method, and could be used for all endoscopes. We also found that the labelled FOV values of many commercial endoscopes are significantly overstated. Our study can help endoscope users understand endoscope FOV and identify a proper method for FOV measurement. This paper can be used as a reference to revise the current endoscope FOV measurement standard. PMID:28663840

  4. Consequences of Family Disruption on Children’s Educational Outcomes in Norway

    PubMed Central

    STEELE, FIONA; SIGLE-RUSHTON, WENDY; KRAVDAL, ØYSTEIN

    2009-01-01

    Using high-quality data from Norwegian population registers, we examine the relationship between family disruption and children’s educational outcomes. We distinguish between disruptions caused by parental divorce and paternal death and, using a simultaneous equation model, pay particular attention to selection bias in the effect of divorce. We also allow for the possibility that disruption may have different effects at different stages of a child’s educational career. Our results suggest that selection on time-invariant maternal characteristics is important and works to overstate the effects of divorce on a child’s chances of continuing in education. Nevertheless, the experience of marital breakdown during childhood is associated with lower levels of education, and the effect weakens with the child’s age at disruption. The effects of divorce are most pronounced for the transitions during or just beyond the high school level. In models that do not allow for selection, children who experienced a father’s death appear less disadvantaged than children whose parents divorced. After we control for selection, however, differences in the educational qualifications of children from divorced and bereaved families narrow substantially and, at mean ages of divorce, are almost non-existent. PMID:19771944

  5. Is It Necessary to Lie to Win a Controversial Public Debate? An Answer from Sociophysics

    NASA Astrophysics Data System (ADS)

    Galam, Serge

    Controversial public debates driven by incomplete scientific data where nobody can claim absolute certainty, due to the current state of scientific knowledge, are studied. To adopt a cautious balanced attitude based on clear but inconclusive data appears to be a lose-out strategy. In contrast overstating arguments with incorrect claims which cannot be scientifically refuted appears to be necessary but not sufficient to eventually win a public debate. The underlying key mechanisms of these puzzling and unfortunate conclusions are identified using the Galam Unifying Frame (GUF) of opinion dynamics . It reveals that the existence of inflexible agents and their respective proportions are the instrumental parameters to determine the faith of incomplete scientific data in public debates. Acting on one's own inflexible proportion modifies the topology of the flow diagram, which in turn can make irrelevant the value of initial support. On the contrary focusing on open-minded agents may be useless given some topologies. Accordingly, the inflexibles rather than the data are found to drive the opinion of the population. The results shed a new but disturbing light on designing adequate strategies to win a public debate. The cases of global warming is briefly discussed.

  6. Design of a feedback-feedforward steering controller for accurate path tracking and stability at the limits of handling

    NASA Astrophysics Data System (ADS)

    Kapania, Nitin R.; Gerdes, J. Christian

    2015-12-01

    This paper presents a feedback-feedforward steering controller that simultaneously maintains vehicle stability at the limits of handling while minimising lateral path tracking deviation. The design begins by considering the performance of a baseline controller with a lookahead feedback scheme and a feedforward algorithm based on a nonlinear vehicle handling diagram. While this initial design exhibits desirable stability properties at the limits of handling, the steady-state path deviation increases significantly at highway speeds. Results from both linear and nonlinear analyses indicate that lateral path tracking deviations are minimised when vehicle sideslip is held tangent to the desired path at all times. Analytical results show that directly incorporating this sideslip tangency condition into the steering feedback dramatically improves lateral path tracking, but at the expense of poor closed-loop stability margins. However, incorporating the desired sideslip behaviour into the feedforward loop creates a robust steering controller capable of accurate path tracking and oversteer correction at the physical limits of tyre friction. Experimental data collected from an Audi TTS test vehicle driving at the handling limits on a full length race circuit demonstrates the improved performance of the final controller design.

  7. Two-photon fluorescent sensor for K+ imaging in live cells (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Sui, Binglin; Yue, Xiling; Kim, Bosung; Belfield, Kevin D.

    2016-03-01

    It is difficult to overstate the physiological importance of potassium for life as its indispensable roles in a variety of biological processes are widely known. As a result, efficient methods for determining physiological levels of potassium are of paramount importance. Despite this, relatively few K+ fluorescence sensors have been reported, with only one being commercially available. A new two-photon excited fluorescent K+ sensor is reported. The sensor is comprised of three moieties, a highly selective K+ chelator as the K+ recognition unit, a boron-dipyrromethene (BODIPY) derivative modified with phenylethynyl groups as the fluorophore, and two polyethylene glycol chains to afford water solubility. The sensor displays very high selectivity (<52-fold) in detecting K+ over other physiological metal cations. Upon binding K+, the sensor switches from non-fluorescent to highly fluorescent, emitting red to near-IR (NIR) fluorescence. The sensor exhibited a good two-photon absorption cross section, 500 GM at 940 nm. Moreover, it is not sensitive to pH in the physiological pH range. Time-dependent cell imaging studies via both one- and two-photon fluorescence microscopy demonstrate that the sensor is suitable for dynamic K+ sensing in living cells.

  8. Healing Africa? Reflections on the peace-building role of a health-based non governmental organization operating in eastern Democratic Republic of Congo.

    PubMed

    D'Errico, Nicole C; Wake, Christopher M; Wake, Rachel M

    2010-01-01

    Whilst there are convincing theoretical arguments about the peace-building potential of the health sector, case studies documenting its interventions remain limited. This article contributes to the existing 'Peace through Health' literature by considering the model of HEAL Africa, a health-based non-governmental organization operating in Eastern Congo. Several of HEAL Africa's projects seek to prevent and reduce key risk factors; for conflict, and to contribute to longer term rehabilitation. Many of these interventions are born out of HEAL's emphasis on providing emergency health care--and the neutrality, legitimacy, access and longevity which this generates. However, this focus also tends to act as a limiting factor on the application and resourcing of its conflict prevention and reconstruction efforts. Whilst this case study warns against overstating the potential role of the health sector in promoting peace, HEAL's activities provide evidence of the types of positive contributions that can be made in practice. The role of the health sector, equipped as it is with useful tools for conflict transformation, should therefore be considered more proactively by the peace-building community.

  9. The compelling case for indentation as a functional exploratory and characterization tool

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tandon, Rajan; Marshall, David B.; Cook, Robert F.

    The utility of indentation testing for characterizing a wide range of mechanical properties of brittle materials is highlighted in light of recent articles questioning its validity, specifically in relation to the measurement of toughness. Contrary to assertion by some critics, indentation fracture theory is fundamentally founded in Griffith–Irwin fracture mechanics, based on model crack systems evolving within inhomogeneous but well-documented elastic and elastic–plastic contact stress fields. Notwithstanding some numerical uncertainty in associated stress intensity factor relations, the technique remains an unrivalled quick, convenient and economical means for comparative, site-specific toughness evaluation. Most importantly, indentation patterns are unique fingerprints of mechanicalmore » behavior and thereby afford a powerful functional tool for exploring the richness of material diversity. At the same time, it is cautioned that unconditional usage without due attention to the conformation of the indentation patterns can lead to overstated toughness values. Limitations of an alternative, more engineering approach to fracture evaluation, that of propagating a precrack through a “standard” machined specimen, are also outlined. Thus misconceptions in the critical literature concerning the fundamental nature of crack equilibrium and stability within contact and other inhomogeneous stress fields are discussed.« less

  10. The compelling case for indentation as a functional exploratory and characterization tool

    DOE PAGES

    Tandon, Rajan; Marshall, David B.; Cook, Robert F.; ...

    2015-07-30

    The utility of indentation testing for characterizing a wide range of mechanical properties of brittle materials is highlighted in light of recent articles questioning its validity, specifically in relation to the measurement of toughness. Contrary to assertion by some critics, indentation fracture theory is fundamentally founded in Griffith–Irwin fracture mechanics, based on model crack systems evolving within inhomogeneous but well-documented elastic and elastic–plastic contact stress fields. Notwithstanding some numerical uncertainty in associated stress intensity factor relations, the technique remains an unrivalled quick, convenient and economical means for comparative, site-specific toughness evaluation. Most importantly, indentation patterns are unique fingerprints of mechanicalmore » behavior and thereby afford a powerful functional tool for exploring the richness of material diversity. At the same time, it is cautioned that unconditional usage without due attention to the conformation of the indentation patterns can lead to overstated toughness values. Limitations of an alternative, more engineering approach to fracture evaluation, that of propagating a precrack through a “standard” machined specimen, are also outlined. Thus misconceptions in the critical literature concerning the fundamental nature of crack equilibrium and stability within contact and other inhomogeneous stress fields are discussed.« less

  11. Nonlinear convective analysis of a rotating Oldroyd-B nanofluid layer under thermal non-equilibrium utilizing Al2O3-EG colloidal suspension

    NASA Astrophysics Data System (ADS)

    Agarwal, Shilpi; Rana, Puneet

    2016-04-01

    In this paper, we examine a layer of Oldroyd-B nanofluid for linear and nonlinear regimes under local thermal non-equilibrium conditions for the classical Rayleigh-Bénard problem. The free-free boundary condition has been implemented with the flux for nanoparticle concentration being zero at edges. The Oberbeck-Boussinesq approximation holds good and for the rotational effect Coriolis term is included in the momentum equation. A two-temperature model explains the effect of local thermal non-equilibrium among the particle and fluid phases. The criteria for onset of stationary convection has been derived as a function of the non-dimensionalized parameters involved including the Taylor number. The assumed boundary conditions negate the possibility of overstability due to the absence of opposing forces responsible for it. The thermal Nusselt number has been obtained utilizing a weak nonlinear theory in terms of various pertinent parameters in the steady and transient mode, and has been depicted graphically. The main findings signify that the rotation has a stabilizing effect on the system. The stress relaxation parameter λ_1 inhibits whereas the strain retardation parameter λ_2 exhibits heat transfer utilizing Al2O3 nanofluids.

  12. The effects of hospice coverage on Medicare expenditures.

    PubMed Central

    Kidder, D

    1992-01-01

    This article reports on the findings of a study of the effects of the hospice program on Medicare Part A expenditures during the first three years of the program. The analysis compared treatment costs between hospice beneficiaries and nonbenefit patients with diagnosis of malignant cancer during their last seven months of life. It was estimated that during the first three years of the hospice program, Medicare saved $1.26 for every dollar spent on Part A expenditures. While the methodology included use of data from Medicare claims to adjust for confounding factors, including self-selection bias, our estimated savings might still have been overstated due to persistent selection effects. The extent of savings also varied according to the hospice's organization. Freestanding hospices, in contrast to those affiliated with either a hospital, nursing home, or home health agency, achieved the greatest savings by utilizing home care more extensively. However, we note that payment rates are increasing and the limits on the benefit period are being lifted, making it possible that the savings related to the hospice program found in this study will not continue. Of greater importance may be the long-term access and quality effects engendered by the benefit's preference for home care. PMID:1592605

  13. New use of global warming potentials to compare cumulative and short-lived climate pollutants

    NASA Astrophysics Data System (ADS)

    Allen, Myles R.; Fuglestvedt, Jan S.; Shine, Keith P.; Reisinger, Andy; Pierrehumbert, Raymond T.; Forster, Piers M.

    2016-08-01

    Parties to the United Nations Framework Convention on Climate Change (UNFCCC) have requested guidance on common greenhouse gas metrics in accounting for Nationally determined contributions (NDCs) to emission reductions. Metric choice can affect the relative emphasis placed on reductions of `cumulative climate pollutants' such as carbon dioxide versus `short-lived climate pollutants' (SLCPs), including methane and black carbon. Here we show that the widely used 100-year global warming potential (GWP100) effectively measures the relative impact of both cumulative pollutants and SLCPs on realized warming 20-40 years after the time of emission. If the overall goal of climate policy is to limit peak warming, GWP100 therefore overstates the importance of current SLCP emissions unless stringent and immediate reductions of all climate pollutants result in temperatures nearing their peak soon after mid-century, which may be necessary to limit warming to ``well below 2 °C'' (ref. ). The GWP100 can be used to approximately equate a one-off pulse emission of a cumulative pollutant and an indefinitely sustained change in the rate of emission of an SLCP. The climate implications of traditional CO2-equivalent targets are ambiguous unless contributions from cumulative pollutants and SLCPs are specified separately.

  14. History and tradition, or contemporary ornithology? Why ornithological journals should not have bird names

    USGS Publications Warehouse

    Remsen, J.V.; Kushlan, J.A.; Loiselle, B.A.

    1998-01-01

    Ask any non-ornithologist to predict the prestige of the following journals, based on the name alone: American Birds, Auk, Bluebird, Condor, Emu, Forktail, Gerfaut, Ibis, Journal of Avian Biology, and Journal of Field Ornithology. The results always will be that the first one and the last two are placed in one category, and the blizzard of bird-named journals in another, lower category. When that same non-ornithologist is called upon to evaluate the publication records of ornithologists, those with important papers in bird-named journals likely will suffer lower rankings. If lucky, an ornithologist under review will receive support from an internationally distinguished ornithological colleague who will take explicit pains to argue that publication in The Auk is a meritorious professional accomplishment. Such arguments, however, may not counteract the damage of a single referee's sneering at the names of the journals in which a bird biologist has chosen to publish. One cannot overstate the importance of the serendipitous collection of peer reviews that determines whether ornithologists get and then keep their first academic jobs, receive tenure, are promoted, are evaluated fairly, and, most important, achieve and maintain the respect of colleagues in other biological disciplines.

  15. Do men’s faces really signal heritable immunocompetence?

    PubMed Central

    2013-01-01

    In the literature on human mate choice, masculine facial morphology is often proposed to be an intersexual signal of heritable immunocompetence, and hence an important component of men’s attractiveness. This hypothesis has received considerable research attention, and is increasingly treated as plausible and well supported. In this article, we propose that the strength of the evidence for the immunocompetence hypothesis is somewhat overstated, and that a number of difficulties have been under-acknowledged. Such difficulties include (1) the tentative nature of the evidence regarding masculinity and disease in humans, (2) the complex and uncertain picture emerging from the animal literature on sexual ornaments and immunity, (3) the absence of consistent, cross-cultural support for the predictions of the immunocompetence hypothesis regarding preferences for masculinized stimuli, and (4) evidence that facial masculinity contributes very little, if anything, to overall attractiveness in real men. Furthermore, alternative explanations for patterns of preferences, in particular the proposal that masculinity is primarily an intrasexual signal, have been neglected. We suggest that immunocompetence perspectives on masculinity, whilst appealing in many ways, should still be regarded as speculative, and that other perspectives–and other traits–should be the subject of greater attention for researchers studying human mate preferences. PMID:23555177

  16. Electronic cigarettes: achieving a balanced perspective.

    PubMed

    Wagener, Theodore L; Siegel, Michael; Borrelli, Belinda

    2012-09-01

    Concerns have been raised that the advent of electronic cigarettes (e-cigarettes) may be harmful to public health, and smokers have been advised by important agencies such as the US Food and Drug Administration not to use them. This paper argues that, while more research is needed on the cost-benefit equation of these products and the appropriate level and type of regulation for them, the harms have tended thus far to be overstated relative to the potential benefits. In particular: concern over repeated inhalation of propylene glycol is not borne out by toxicity studies with this compound; risk of accidental poisoning is no different from many household devices and chemicals available in supermarkets; concern that e-cigarettes may promote continued smoking by allowing smokers to cope with no-smoking environments is countered by the observation that most smokers use these products to try to quit and their use appears to enhance quitting motivation; concerns over low nicotine delivery are countered by evidence that the products provide significant craving reduction despite this in some cases; and e-cigarettes may help reduce toxin exposure to non-smokers. © 2012 The Authors. Addiction © 2012 Society for the Study of Addiction.

  17. The politics of assessment: water and sanitation MDGs in the Middle East.

    PubMed

    Zawahri, Neda; Sowers, Jeannie; Weinthal, Erika

    2011-01-01

    The Middle East and North Africa (MENA) is generally considered to be making adequate progress towards meeting Target 10 of the Millennium Development Goals (MDGs), which calls for halving the proportion of the population with inadequate access to drinking water and sanitation. Progress towards achieving Target 10 is evaluated by the Joint Monitoring Programme (JMP), run by UNICEF and WHO. This article shows that the assessment methodologies employed by the JMP significantly overstate coverage rates in the drinking water and sanitation sectors, by overlooking and ‘not counting’ problems of access, affordability, quality of service and pollution. The authors show that states in MENA often fail to provide safe drinking water and adequate sanitation services, particularly in densely populated informal settlements, and that many centralized water and sanitation infrastructures contribute to water pollution and contamination. Despite the glaring gap between the MDG statistics and the evidence available from national and local reports, exclusionary political regimes in the region have had few incentives to adopt more accurate assessments and improve the quality of service. While international organizations have proposed some reforms, they too lack incentives to employ adequate measures that gauge access, quality and affordability of drinking water and sanitation services.

  18. Devaluation, crowding or skill specificity? Exploring the mechanisms behind the lower wages in female professions.

    PubMed

    Grönlund, Anne; Magnusson, Charlotta

    2013-07-01

    A conspicuous finding in research on the gender wage gap is that wages are related to the percentage females in an occupation (percent F). Three mechanisms have been suggested to explain this relationship: a devaluation of women's work, a crowding of women into a limited number of occupations, and a female disadvantage in the accumulation of specific human capital. In this analysis, based on data from the Swedish Level of Living Survey of 2000 (n=2915), we distinguish between these mechanisms using measures of devaluation (Treiman's prestige scale), crowding (employee dependence on current employer) and specific human capital (on-the-job training). The results show that all the indicators are related to percent F, but not in a linear fashion, and that the percent F-effect on wages is overstated and misspecified. Female-dominated occupations stand out with lower wages than both male-dominated and gender-integrated occupations and this is not explained by any of our measures. Thus, if the hypotheses on segregation and wages should be sustained, they must be further specified and new measures must be found to prove their worth. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. The effects of hospice coverage on Medicare expenditures.

    PubMed

    Kidder, D

    1992-06-01

    This article reports on the findings of a study of the effects of the hospice program on Medicare Part A expenditures during the first three years of the program. The analysis compared treatment costs between hospice beneficiaries and nonbenefit patients with diagnosis of malignant cancer during their last seven months of life. It was estimated that during the first three years of the hospice program, Medicare saved $1.26 for every dollar spent on Part A expenditures. While the methodology included use of data from Medicare claims to adjust for confounding factors, including self-selection bias, our estimated savings might still have been overstated due to persistent selection effects. The extent of savings also varied according to the hospice's organization. Freestanding hospices, in contrast to those affiliated with either a hospital, nursing home, or home health agency, achieved the greatest savings by utilizing home care more extensively. However, we note that payment rates are increasing and the limits on the benefit period are being lifted, making it possible that the savings related to the hospice program found in this study will not continue. Of greater importance may be the long-term access and quality effects engendered by the benefit's preference for home care.

  20. Life imitating art: depictions of the hidden curriculum in medical television programs.

    PubMed

    Stanek, Agatha; Clarkin, Chantalle; Bould, M Dylan; Writer, Hilary; Doja, Asif

    2015-09-26

    The hidden curriculum represents influences occurring within the culture of medicine that indirectly alter medical professionals' interactions, beliefs and clinical practices throughout their training. One approach to increase medical student awareness of the hidden curriculum is to provide them with readily available examples of how it is enacted in medicine; as such the purpose of this study was to examine depictions of the hidden curriculum in popular medical television programs. One full season of ER, Grey's Anatomy and Scrubs were selected for review. A summative content analysis was performed to ascertain the presence of depictions of the hidden curriculum, as well as to record the type, frequency and quality of examples. A second reviewer also viewed a random selection of episodes from each series to establish coding reliability. The most prevalent themes across all television programs were: the hierarchical nature of medicine; challenges during transitional stages in medicine; the importance of role modeling; patient dehumanization; faking or overstating one's capabilities; unprofessionalism; the loss of idealism; and difficulties with work-life balance. The hidden curriculum is frequently depicted in popular medical television shows. These examples of the hidden curriculum could serve as a valuable teaching resource in undergraduate medical programs.

  1. An evaluation of criteria that may be used to identify species surviving a mass extinction

    NASA Technical Reports Server (NTRS)

    Macleod, N.

    1994-01-01

    One of the most difficult obstacles to establishing a causal connection between mass extinctions and large body impacts is the existence of what appear to be many more KT survivor species than previously suspected. Though interpretations of 'Cretaceous' faunal elements in lowermost Danian sediments differ, this enigmatic fauna has not been recovered from every biozone-complete boundary section, including the El Kef stratotype. In terms of their potential for providing constraints on scenarios seeking to account for the KT extinction event, the significance of such observations cannot be overstated. Owing to the consistency with which these observations have been made over the last several years, the possibility of widespread trans-KT biotic survivorship can no longer be dismissed. Rather, the survivorship hypothesis must be tested alongside its alternative (the reworking hypothesis) to determine which explains the available data in the most complete yet parsimonious manner. Moreover, valid tests for survivorship cannot be based on negative evidence or on the assumption that only a small cohort of species could have survived the KT boundary event. Several authors have recently proposed various criteria that might be used to test alternative interpretations for this aspect lowermost Danian biotic record.

  2. Evaluation of the apparent losses caused by water meter under-registration in intermittent water supply.

    PubMed

    Criminisi, A; Fontanazza, C M; Freni, G; Loggia, G La

    2009-01-01

    Apparent losses are usually caused by water theft, billing errors, or revenue meter under-registration. While the first two causes are directly related to water utility management and may be reduced by improving company procedures, water meter inaccuracies are considered to be the most significant and hardest to quantify. Water meter errors are amplified in networks subjected to water scarcity, where users adopt private storage tanks to cope with the intermittent water supply. The aim of this paper is to analyse the role of two variables influencing the apparent losses: water meter age and the private storage tank effect on meter performance. The study was carried out in Palermo (Italy). The impact of water meter ageing was evaluated in laboratory by testing 180 revenue meters, ranging from 0 to 45 years in age. The effects of the private water tanks were determined via field monitoring of real users and a mathematical model. This study demonstrates that the impact on apparent losses from the meter starting flow rapidly increases with meter age. Private water tanks, usually fed by a float valve, overstate meter under-registration, producing additional apparent losses between 15% and 40% for the users analysed in this study.

  3. The importance of adjusting for trip purpose in regional economic analyses of tourist destinations

    USGS Publications Warehouse

    Loomis, J.; Caughlan, L.

    2006-01-01

    This paper investigates the empirical importance of distinguishing visitors and their expenditures by trip purpose when estimating the tourism effects of a national park on a local economy. Accounting for trip purpose is quite important when there are two or more nearby major attractions in the same geographical area. This applies to the author's case study of Grand Teton and Yellowstone National Parks in the State of Wyoming, and also to other areas, such as the State of Utah's Bryce and Zion National Parks or amusement parks in the Orlando area in Florida. The authors illustrate the various types of survey questions and methods for correcting for trip purpose. In the case study, it would be quite misleading to attribute all spending by visitors to Grand Teton National Park (GTNP) in the town of Jackson, Wyoming, solely to GTNP because this would overstate employment actually attributable to the park by 3,455 jobs, or 22%. In turn, this overestimates the dependence of jobs in the Jackson economy on GTNP by 15%, incorrectly estimating it at 75% rather than the sounder figure of 60% of total jobs.

  4. Problems with the Fraser report Chapter 1: Pitfalls in BMI time trend analysis.

    PubMed

    Lo, Ernest

    2014-11-05

    The first chapter of the Fraser report "Obesity in Canada: Overstated Problems, Misguided Policy Solutions" presents a flawed and misleading analysis of BMI time trends. The objective of this commentary is to provide a tutorial on BMI time trend analysis through the examination of these flaws. Three issues are discussed: 1. Spotting regions of confidence interval overlap is a statistically flawed method of assessing trend; regression methods which measure the behaviour of the data as a whole are preferred. 2. Temporal stability in overweight (25≤BMI<30) prevalence must be interpreted in the context of the underlying population BMI distribution. 3. BMI is considered reliable for tracking population-level weight trends due to its high correlation with body fat percentage. BMI-defined obesity prevalence represents a conservative underestimate of the population at risk. The findings of the Fraser report Chapter 1 are either refuted or substantially mitigated once the above issues are accounted for, and we do not find that the 'Canadian situation largely lacks a disconcerting or negative trend', as claimed. It is hoped that this commentary will help guide public health professionals who need to interpret, or wish to perform their own, time trend analyses of BMI.

  5. Why are conservatives more punitive than liberals? A moral foundations approach.

    PubMed

    Silver, Jasmine R; Silver, Eric

    2017-06-01

    Morality is thought to underlie both ideological and punitive attitudes. In particular, moral foundations research suggests that group-oriented moral concerns promote a conservative orientation, while individual-oriented moral concerns promote a liberal orientation (Graham, Haidt, & Nosek, 2009). Drawing on classical sociological theory, we argue that endorsement of group-oriented moral concerns also elicits higher levels of punitiveness by promoting a view of crime as being perpetrated against society, while endorsement of individual-oriented moral concerns reduces punitiveness by directing attention toward the welfare of offenders as well as victims. Data from 2 independent samples (N = 1,464 and N = 1,025) showed that endorsement of group-oriented moral concerns was associated with more punitive and more conservative attitudes, while endorsement of individual-oriented moral concerns was associated with less punitive and less conservative attitudes. These results suggest that the association between conservatism and punitiveness is in part spurious because of their grounding in the moral foundations. Consequently, studies that do not take the moral foundations into account are at risk of overstating the relationship between conservatism and punitiveness. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  6. Estimating the benefits of public health policies that reduce harmful consumption.

    PubMed

    Ashley, Elizabeth M; Nardinelli, Clark; Lavaty, Rosemarie A

    2015-05-01

    For products such as tobacco and junk food, where policy interventions are often designed to decrease consumption, affected consumers gain utility from improvements in lifetime health and longevity but also lose utility associated with the activity of consuming the product. In the case of anti-smoking policies, even though published estimates of gross health and longevity benefits are up to 900 times higher than the net consumer benefits suggested by a more direct willingness-to-pay estimation approach, there is little recognition in the cost-benefit and cost-effectiveness literature that gross estimates will overstate intrapersonal welfare improvements when utility losses are not netted out. This paper presents a general framework for analyzing policies that are designed to reduce inefficiently high consumption and provides a rule of thumb for the relationship between net and gross consumer welfare effects: where there exists a plausible estimate of the tax that would allow consumers to fully internalize health costs, the ratio of the tax to the per-unit long-term cost can provide an upper bound on the ratio of net to gross benefits. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

  7. Stabilizing g-States in Centrosymmetric Tetrapyrroles: Two-Photon-Absorbing Porphyrins with Bright Phosphorescence.

    PubMed

    Esipova, Tatiana V; Rivera-Jacquez, Héctor J; Weber, Bruno; Masunov, Artëm E; Vinogradov, Sergei A

    2017-08-24

    Using time-dependent density functional theory (TDDFT) and sum-overstates (SOS) formalism, we predicted significant stabilization of 2P-active g-states in a compact fully symmetric porphyrin, in which all four pyrrolic fragments are fused with phathalimide residues via the β-carbon positions. The synthesis of a soluble, nonaggregating meso-unsubstituted tetraarylphthalimidoporphyrin (TAPIP) was then developed, and the spectroscopic measurements confirmed that a strongly 2P-active state in this porphyrin is stabilized below the B (Soret) state level. Single-crystal X-ray analysis revealed near-ideally planar geometry of the TAPIP macrocycle, while its tetra-meso-arylated analogue (meso-Ar 4 TAPIP) was found to be highly saddled. Consistent with these structural features, Pt meso-Ar 4 TAPIP phosphoresces rather weakly (ϕ phos = 0.05 in DMF at 22 °C), while both Pt and Pd complexes of TAPIP are highly phosphorescent (ϕ phos = 0.45 and 0.23, respectively). In addition PdTAPIP exhibits non-negligible thermally activated (E-type) delayed fluorescence (ϕ fl (d) ∼ 0.012). Taken together, these photophysical properties make metal complexes of meso-unsubstituted tetaarylphthalimidoporphyrins the brightest 2P-absorbing phosphorescent chromophores known to date.

  8. Limitations of direct-to-consumer advertising for clinical genetic testing.

    PubMed

    Gollust, Sarah E; Hull, Sara Chandros; Wilfond, Benjamin S

    2002-10-09

    Although direct-to-consumer (DTC) advertisements for pharmaceuticals have been appearing in the mass media for 20 years, DTC advertisements for genetic testing have only recently appeared. Advertisements for genetic testing can provide both consumers and physicians with information about test availability in an expanding market. However, 3 factors limit the value and appropriateness of advertisements: complex information, a complicated social context surrounding genetics, and a lack of consensus about the clinical utility of some tests. Consideration of several advertisements suggests that they overstate the value of genetic testing for consumers' clinical care. Furthermore, advertisements may provide misinformation about genetics, exaggerate consumers' risks, endorse a deterministic relationship between genes and disease, and reinforce associations between diseases and ethnic groups. Advertising motivated by factors other than evidence of the clinical value of genetic tests can manipulate consumers' behavior by exploiting their fears and worries. At this time, DTC advertisements are inappropriate, given the public's limited sophistication regarding genetics and the lack of comprehensive premarket review of tests or oversight of advertisement content. Existing Federal Trade Commission and Food and Drug Administration regulations for other types of health-related advertising should be applied to advertisements for genetic tests.

  9. Biogeography of worm lizards (Amphisbaenia) driven by end-Cretaceous mass extinction

    PubMed Central

    Longrich, Nicholas R.; Vinther, Jakob; Pyron, R. Alexander; Pisani, Davide; Gauthier, Jacques A.

    2015-01-01

    Worm lizards (Amphisbaenia) are burrowing squamates that live as subterranean predators. Their underground existence should limit dispersal, yet they are widespread throughout the Americas, Europe and Africa. This pattern was traditionally explained by continental drift, but molecular clocks suggest a Cenozoic diversification, long after the break-up of Pangaea, implying dispersal. Here, we describe primitive amphisbaenians from the North American Palaeocene, including the oldest known amphisbaenian, and provide new and older molecular divergence estimates for the clade, showing that worm lizards originated in North America, then radiated and dispersed in the Palaeogene following the Cretaceous-Palaeogene (K-Pg) extinction. This scenario implies at least three trans-oceanic dispersals: from North America to Europe, from North America to Africa and from Africa to South America. Amphisbaenians provide a striking case study in biogeography, suggesting that the role of continental drift in biogeography may be overstated. Instead, these patterns support Darwin and Wallace's hypothesis that the geographical ranges of modern clades result from dispersal, including oceanic rafting. Mass extinctions may facilitate dispersal events by eliminating competitors and predators that would otherwise hinder establishment of dispersing populations, removing biotic barriers to dispersal. PMID:25833855

  10. Mind over platter: pre-meal planning and the control of meal size in humans.

    PubMed

    Brunstrom, J M

    2014-07-01

    It is widely accepted that meal size is governed by psychological and physiological processes that generate fullness towards the end of a meal. However, observations of natural eating behaviour suggest that this preoccupation with within-meal events may be misplaced and that the role of immediate post-ingestive feedback (for example, gastric stretch) has been overstated. This review considers the proposition that the locus of control is more likely to be expressed in decisions about portion size, before a meal begins. Consistent with this idea, we have discovered that people are extremely adept at estimating the 'expected satiety' and 'expected satiation' of different foods. These expectations are learned over time and they are highly correlated with the number of calories that end up on our plate. Indeed, across a range of foods, the large variation in expected satiety/satiation may be a more important determinant of meal size than relatively subtle differences in palatability. Building on related advances, it would also appear that memory for portion size has an important role in generating satiety after a meal has been consumed. Together, these findings expose the importance of planning and episodic memory in the control of appetite and food intake in humans.

  11. Cigarette tax avoidance and evasion.

    PubMed

    Stehr, Mark

    2005-03-01

    Variation in state cigarette taxes provides incentives for tax avoidance through smuggling, legal border crossing to low tax jurisdictions, or Internet purchasing. When taxes rise, tax paid sales of cigarettes will decline both because consumption will decrease and because tax avoidance will increase. The key innovation of this paper is to compare cigarette sales data to cigarette consumption data from the Behavioral Risk Factor Surveillance System (BRFSS). I show that after subtracting percent changes in consumption, residual percent changes in sales are associated with state cigarette tax changes implying the existence of tax avoidance. I estimate that the tax avoidance response to tax changes is at least twice the consumption response and that tax avoidance accounted for up to 9.6% of sales between 1985 and 2001. Because of the increase in tax avoidance, tax paid sales data understate the level of smoking and overstate the drop in smoking. I also find that the level of legal border crossing was very low relative to other forms of tax avoidance. If states have strong preferences for smoking control, they must pair high cigarette taxes with effective policies to curb smuggling and other forms of tax avoidance or employ alternative policies such as counter-advertising and smoking restrictions.

  12. The Complex Relationship between Virulence and Antibiotic Resistance

    PubMed Central

    Schroeder, Meredith; Brooks, Benjamin D.; Brooks, Amanda E.

    2017-01-01

    Antibiotic resistance, prompted by the overuse of antimicrobial agents, may arise from a variety of mechanisms, particularly horizontal gene transfer of virulence and antibiotic resistance genes, which is often facilitated by biofilm formation. The importance of phenotypic changes seen in a biofilm, which lead to genotypic alterations, cannot be overstated. Irrespective of if the biofilm is single microbe or polymicrobial, bacteria, protected within a biofilm from the external environment, communicate through signal transduction pathways (e.g., quorum sensing or two-component systems), leading to global changes in gene expression, enhancing virulence, and expediting the acquisition of antibiotic resistance. Thus, one must examine a genetic change in virulence and resistance not only in the context of the biofilm but also as inextricably linked pathologies. Observationally, it is clear that increased virulence and the advent of antibiotic resistance often arise almost simultaneously; however, their genetic connection has been relatively ignored. Although the complexities of genetic regulation in a multispecies community may obscure a causative relationship, uncovering key genetic interactions between virulence and resistance in biofilm bacteria is essential to identifying new druggable targets, ultimately providing a drug discovery and development pathway to improve treatment options for chronic and recurring infection. PMID:28106797

  13. Failures of reproduction: problematising 'success' in assisted reproductive technology.

    PubMed

    Peters, Kathleen; Jackson, Debra; Rudge, Trudy

    2007-06-01

    This paper scrutinises the many ways in which 'success' is portrayed in representing assisted reproductive technology (ART) services and illuminates how these definitions differ from those held by participant couples. A qualitative approach informed by feminist perspectives guided this study and aimed to problematise the concept of 'success' by examining literature from ART clinics, government reports on ART, and by analysing narratives of couples who have accessed ART services. As many ART services have varying definitions of 'success' and as statistics are manipulated to promote further patronage of ART services, the likelihood of 'success' is often overstated. This paper is concerned with the effects this promotion has on the participants. We suggest that this very mobilisation of statistical success changes the ability of those who access ART services to make productive decisions about themselves inside these treatment regimes, as the basis for decision-making is hidden by the way numbers, objectivity and clinical reasoning operate to maintain participation in the program. In such an operation, the powerful mix of hope and technology kept participants enrolled far longer than they originally planned. Moreover, how success rates are manipulated raises ethical issues for all involved: clients, counsellors, and nursing and medical professionals.

  14. Ideal, nonideal, and no-marker variables: The confirmatory factor analysis (CFA) marker technique works when it matters.

    PubMed

    Williams, Larry J; O'Boyle, Ernest H

    2015-09-01

    A persistent concern in the management and applied psychology literature is the effect of common method variance on observed relations among variables. Recent work (i.e., Richardson, Simmering, & Sturman, 2009) evaluated 3 analytical approaches to controlling for common method variance, including the confirmatory factor analysis (CFA) marker technique. Their findings indicated significant problems with this technique, especially with nonideal marker variables (those with theoretical relations with substantive variables). Based on their simulation results, Richardson et al. concluded that not correcting for method variance provides more accurate estimates than using the CFA marker technique. We reexamined the effects of using marker variables in a simulation study and found the degree of error in estimates of a substantive factor correlation was relatively small in most cases, and much smaller than error associated with making no correction. Further, in instances in which the error was large, the correlations between the marker and substantive scales were higher than that found in organizational research with marker variables. We conclude that in most practical settings, the CFA marker technique yields parameter estimates close to their true values, and the criticisms made by Richardson et al. are overstated. (c) 2015 APA, all rights reserved).

  15. Biogeography of worm lizards (Amphisbaenia) driven by end-Cretaceous mass extinction.

    PubMed

    Longrich, Nicholas R; Vinther, Jakob; Pyron, R Alexander; Pisani, Davide; Gauthier, Jacques A

    2015-05-07

    Worm lizards (Amphisbaenia) are burrowing squamates that live as subterranean predators. Their underground existence should limit dispersal, yet they are widespread throughout the Americas, Europe and Africa. This pattern was traditionally explained by continental drift, but molecular clocks suggest a Cenozoic diversification, long after the break-up of Pangaea, implying dispersal. Here, we describe primitive amphisbaenians from the North American Palaeocene, including the oldest known amphisbaenian, and provide new and older molecular divergence estimates for the clade, showing that worm lizards originated in North America, then radiated and dispersed in the Palaeogene following the Cretaceous-Palaeogene (K-Pg) extinction. This scenario implies at least three trans-oceanic dispersals: from North America to Europe, from North America to Africa and from Africa to South America. Amphisbaenians provide a striking case study in biogeography, suggesting that the role of continental drift in biogeography may be overstated. Instead, these patterns support Darwin and Wallace's hypothesis that the geographical ranges of modern clades result from dispersal, including oceanic rafting. Mass extinctions may facilitate dispersal events by eliminating competitors and predators that would otherwise hinder establishment of dispersing populations, removing biotic barriers to dispersal. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  16. Modelling Quasi-Periodic Pulsations in Solar and Stellar Flares

    NASA Astrophysics Data System (ADS)

    McLaughlin, J. A.; Nakariakov, V. M.; Dominique, M.; Jelínek, P.; Takasao, S.

    2018-02-01

    Solar flare emission is detected in all EM bands and variations in flux density of solar energetic particles. Often the EM radiation generated in solar and stellar flares shows a pronounced oscillatory pattern, with characteristic periods ranging from a fraction of a second to several minutes. These oscillations are referred to as quasi-periodic pulsations (QPPs), to emphasise that they often contain apparent amplitude and period modulation. We review the current understanding of quasi-periodic pulsations in solar and stellar flares. In particular, we focus on the possible physical mechanisms, with an emphasis on the underlying physics that generates the resultant range of periodicities. These physical mechanisms include MHD oscillations, self-oscillatory mechanisms, oscillatory reconnection/reconnection reversal, wave-driven reconnection, two loop coalescence, MHD flow over-stability, the equivalent LCR-contour mechanism, and thermal-dynamical cycles. We also provide a histogram of all QPP events published in the literature at this time. The occurrence of QPPs puts additional constraints on the interpretation and understanding of the fundamental processes operating in flares, e.g. magnetic energy liberation and particle acceleration. Therefore, a full understanding of QPPs is essential in order to work towards an integrated model of solar and stellar flares.

  17. The impact of atopic dermatitis on quality of life.

    PubMed

    Lifschitz, Carlos

    2015-01-01

    Approximately 5-20% of children worldwide suffer from atopic dermatitis (AD), a kind of dermatitis characterized as an inflammatory, relapsing, noncontagious and itchy skin disorder. Children often develop AD during their first year of life. An increased rate of sensitization to both food and aeroallergens has been shown to coexist in patients with AD. Sensitization to well-known allergens such as cow's milk protein can occur on average in 50% of children with AD. In general, quality of life (QoL) is perceived as the quality of an individual's daily life, that is, an assessment of their well-being or lack thereof. QoL is a broad concept that includes such things as standard of living, community, and family life. Patients with skin diseases experience a wide range of symptoms ranging from trivial problems to major handicaps which affect their lives. The misery of living with AD cannot be overstated for it may have a profoundly negative effect on the health-related QoL of children and their families in many cases. Physicians taking care of children with AD should consult parents on how their child's illness has impacted their lifestyle and recommend professional intervention if deemed necessary. © 2015 S. Karger AG, Basel.

  18. District nursing workforce planning: a review of the methods.

    PubMed

    Reid, Bernie; Kane, Kay; Curran, Carol

    2008-11-01

    District nursing services in Northern Ireland face increasing demands and challenges which may be responded to by effective and efficient workforce planning and development. The aim of this paper is to critically analyse district nursing workforce planning and development methods, in an attempt to find a suitable method for Northern Ireland. A systematic analysis of the literature reveals four methods: professional judgement; population-based health needs; caseload analysis and dependency-acuity. Each method has strengths and weaknesses. Professional judgement offers a 'belt and braces' approach but lacks sensitivity to fluctuating patient numbers. Population-based health needs methods develop staffing algorithms that reflect deprivation and geographical spread, but are poorly understood by district nurses. Caseload analysis promotes equitable workloads but poorly performing district nursing localities may continue if benchmarking processes only consider local data. Dependency-acuity methods provide a means of equalizing and prioritizing workload but are prone to district nurses overstating factors in patient dependency or understating carers' capability. In summary a mixed method approach is advocated to evaluate and adjust the size and mix of district nursing teams using empirically determined patient dependency and activity-based variables based on the population's health needs.

  19. THE NICHE CONSTRUCTION PERSPECTIVE: A CRITICAL APPRAISAL*

    PubMed Central

    Scott-Phillips, Thomas C; Laland, Kevin N; Shuker, David M; Dickins, Thomas E; West, Stuart A

    2014-01-01

    Niche construction refers to the activities of organisms that bring about changes in their environments, many of which are evolutionarily and ecologically consequential. Advocates of niche construction theory (NCT) believe that standard evolutionary theory fails to recognize the full importance of niche construction, and consequently propose a novel view of evolution, in which niche construction and its legacy over time (ecological inheritance) are described as evolutionary processes, equivalent in importance to natural selection. Here, we subject NCT to critical evaluation, in the form of a collaboration between one prominent advocate of NCT, and a team of skeptics. We discuss whether niche construction is an evolutionary process, whether NCT obscures or clarifies how natural selection leads to organismal adaptation, and whether niche construction and natural selection are of equivalent explanatory importance. We also consider whether the literature that promotes NCT overstates the significance of niche construction, whether it is internally coherent, and whether it accurately portrays standard evolutionary theory. Our disagreements reflect a wider dispute within evolutionary theory over whether the neo-Darwinian synthesis is in need of reformulation, as well as different usages of some key terms (e.g., evolutionary process). PMID:24325256

  20. Overview of the TriBITS Lifecycle Model: Lean/Agile Software Lifecycle Model for Research-based Computational Science and Engineering Software

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bartlett, Roscoe A; Heroux, Dr. Michael A; Willenbring, James

    2012-01-01

    Software lifecycles are becoming an increasingly important issue for computational science & engineering (CSE) software. The process by which a piece of CSE software begins life as a set of research requirements and then matures into a trusted high-quality capability is both commonplace and extremely challenging. Although an implicit lifecycle is obviously being used in any effort, the challenges of this process--respecting the competing needs of research vs. production--cannot be overstated. Here we describe a proposal for a well-defined software lifecycle process based on modern Lean/Agile software engineering principles. What we propose is appropriate for many CSE software projects thatmore » are initially heavily focused on research but also are expected to eventually produce usable high-quality capabilities. The model is related to TriBITS, a build, integration and testing system, which serves as a strong foundation for this lifecycle model, and aspects of this lifecycle model are ingrained in the TriBITS system. Indeed this lifecycle process, if followed, will enable large-scale sustainable integration of many complex CSE software efforts across several institutions.« less

  1. Showing Value in Newborn Screening: Challenges in Quantifying the Effectiveness and Cost-Effectiveness of Early Detection of Phenylketonuria and Cystic Fibrosis

    PubMed Central

    Grosse, Scott D.

    2015-01-01

    Decision makers sometimes request information on the cost savings, cost-effectiveness, or cost-benefit of public health programs. In practice, quantifying the health and economic benefits of population-level screening programs such as newborn screening (NBS) is challenging. It requires that one specify the frequencies of health outcomes and events, such as hospitalizations, for a cohort of children with a given condition under two different scenarios—with or without NBS. Such analyses also assume that everything else, including treatments, is the same between groups. Lack of comparable data for representative screened and unscreened cohorts that are exposed to the same treatments following diagnosis can result in either under- or over-statement of differences. Accordingly, the benefits of early detection may be understated or overstated. This paper illustrates these common problems through a review of past economic evaluations of screening for two historically significant conditions, phenylketonuria and cystic fibrosis. In both examples qualitative judgments about the value of prompt identification and early treatment to an affected child were more influential than specific numerical estimates of lives or costs saved. PMID:26702401

  2. Optimization of vehicle-trailer connection systems

    NASA Astrophysics Data System (ADS)

    Sorge, F.

    2016-09-01

    The three main requirements of a vehicle-trailer connection system are: en route stability, over- or under-steering restraint, minimum off-tracking along curved path. Linking the two units by four-bar trapeziums, wider stability margins may be attained in comparison with the conventional pintle-hitch for both instability types, divergent or oscillating. The stability maps are traced applying the Hurwitz method or the direct analysis of the characteristic equation at the instability threshold. Several types of four-bar linkages may be quickly tested, with the drawbars converging towards the trailer or the towing unit. The latter configuration appears preferable in terms of self-stability and may yield high critical speeds by optimising the geometrical and physical properties. Nevertheless, the system stability may be improved in general by additional vibration dampers in parallel with the connection linkage. Moreover, the four-bar connection may produce significant corrections of the under-steering or over-steering behaviour of the vehicle-train after a steering command from the driver. The off- tracking along the curved paths may be also optimized or kept inside prefixed margins of acceptableness. Activating electronic stability systems if necessary, fair results are obtainable for both the steering conduct and the off-tracking.

  3. Underwhelmed: hyperbole, regulatory policy, and the genetic revolution.

    PubMed

    Caulfield, T

    2000-05-01

    Rapid advances in the field of genetics in recent years have caused some commentators to suggest the emergence of a "genetic revolution." Such advances have been both praised as the "future of medicine" and condemned for encouraging the acceptance in society of laissez-faire eugenics. Yet the effect of technological advances flowing from the science of genetics appear somewhat overstated as few products of the genetic revolution, particularly in the areas of gene therapy and genetic testing, have managed to satisfy scientists' expectations to date. Furthermore, misdirected regulation of such advances can exacerbate the social, legal, and ethical problems associated with genetics, particularly in the context of health care, where issues of human cloning and the use of premature genetic testing technologies dominate current public debate. In this article, the author criticizes the hyperbolic rhetoric surrounding the genetic revolution and calls for a more balanced and informed approach to the development of genetic policies and regulations. Such an approach should include substantial interdisciplinary debate and an active role on the part of government in the identification and communication of accurate information relating to the effects of recent technological advances in the field of genetics.

  4. Neuropsychiatric Effects of Antimicrobial Agents.

    PubMed

    Zareifopoulos, Nicholas; Panayiotakopoulos, George

    2017-05-01

    Antimicrobial drugs used in clinical practice are selected on the basis of their selective toxicity against bacterial cells. However, all exhibit multiple offsite interactions with eukaryotic cell structures, resulting in adverse reactions during antimicrobial pharmacotherapy. A multitude of these side effects involve the nervous system as antimicrobials at clinically relevant concentrations seem to interact with many of the same molecules usually implicated in the action of psychotropic drugs. The importance of such events cannot be overstated, as the misdiagnosis of an adverse drug reaction as a symptom of a primary psychiatric or neurological disorder entails great suffering for the patient affected as well as significant costs for the healthcare system. The neuropsychiatric effects of antimicrobial drugs are extensively documented in the literature. A number of antimicrobial drugs have the potential to exert CNS effects and many are associated with stimulant, psychotomimetic and epileptogenic properties, mediated by GABA antagonism (beta-lactams, quinolones and clarithromycin), NMDA agonism (D-cycloserine, aminoglycosides, and perhaps quinolones), MAO inhibition (linezolid, metronidazole and isoniazid weakly) as well as more exotic mechanisms, as in the case of trimethoprim, isoniazid, ethambutol, rifampicin and the tetracyclines. While those effects are generally undesirable, they may also under certain circumstances be beneficial, and further research is warranted in that direction.

  5. The noncoding human genome and the future of personalised medicine.

    PubMed

    Cowie, Philip; Hay, Elizabeth A; MacKenzie, Alasdair

    2015-01-30

    Non-coding cis-regulatory sequences act as the 'eyes' of the genome and their role is to perceive, organise and relay cellular communication information to RNA polymerase II at gene promoters. The evolution of these sequences, that include enhancers, silencers, insulators and promoters, has progressed in multicellular organisms to the extent that cis-regulatory sequences make up as much as 10% of the human genome. Parallel evidence suggests that 75% of polymorphisms associated with heritable disease occur within predicted cis-regulatory sequences that effectively alter the 'perception' of cis-regulatory sequences or render them blind to cell communication cues. Cis-regulatory sequences also act as major functional targets of epigenetic modification thus representing an important conduit through which changes in DNA-methylation affects disease susceptibility. The objectives of the current review are (1) to describe what has been learned about identifying and characterising cis-regulatory sequences since the sequencing of the human genome; (2) to discuss their role in interpreting cell signalling pathways pathways; and (3) outline how this role may be altered by polymorphisms and epigenetic changes. We argue that the importance of the cis-regulatory genome for the interpretation of cellular communication pathways cannot be overstated and understanding its role in health and disease will be critical for the future development of personalised medicine.

  6. Expanding the use of empiricism in nursing: can we bridge the gap between knowledge and clinical practice?

    PubMed

    Giuliano, Karen K

    2003-04-01

    The philosophy of Aristotle and its impact on the process of empirical scientific inquiry has been substantial. The influence of the clarity and orderliness of his thinking, when applied to the acquisition of knowledge in nursing, can not be overstated. Traditional empirical approaches have and will continue to have an important influence on the development of nursing knowledge through nursing research. However, as nursing is primarily a practice discipline, the transition from empirical and syllogistic reasoning is problematic. Other types of inquiry are essential in the application of nursing knowledge obtained by empirical scientific approaches and to understand how that knowledge can best be used in the care of patients. This paper reviews the strengths and limitations of syllogistic reasoning by applying it to a recently published study on temperature measurement in nursing. It then discusses possible ways that the empirical knowledge gained from that study and confirmed in its reasoning by logical analysis could be used in the daily care of critically ill patients. It concludes by highlighting the utility of broader approaches to knowledge development, including interpretative approaches and contemporary empiricism, as a way to bridge the gap between factual empirical knowledge and the practical application of that knowledge in everyday clinical nursing practice.

  7. Rural Mexican-Americans' perceptions of family health history, genetics, and disease risk: implications for disparities-focused research dissemination.

    PubMed

    Malen, Rachel; Knerr, Sarah; Delgado, Fernanda; Fullerton, Stephanie M; Thompson, Beti

    2016-01-01

    Disseminating the results of transdisciplinary health disparities research will increasingly involve discussing family health history and/or genetic information with study participants and their communities. Often, individuals' familiarity and comfort with these topics will be unclear. To inform the dissemination activities of a Center for Population Health and Health Disparities (CPHHD) studying multilevel determinants of breast cancer disparities in Latinas, we talked with Spanish-speaking Mexican-Americans from a rural agricultural community about family health history, genetics, and disease risk. We found that participants had limited genetic literacy but were familiar with some concepts related to family health history. Participants emphasized the role of individual behavior in shaping health and expressed a strong desire for health-related information. This included genetic information about future disease risk, which participants were previously unaware of but thought could be useful for disease prevention. These findings suggest that for research dissemination to facilitate health promotion, gaps in knowledge, particularly genetic knowledge, will need to be overcome. Outreach to underserved Latino communities should take advantage of this existing knowledge of family health history and strong desire for health information, but also take care to not overstate the significance of unreplicated or low-penetrance genetic associations.

  8. God and the Welfare State - Substitutes or Complements? An Experimental Test of the Effect of Belief in God's Control

    PubMed Central

    Be’ery, Gilad; Ben-Nun Bloom, Pazit

    2015-01-01

    Belief in God’s control of the world is common to many of the world’s religions, but there are conflicting predictions regarding its role in shaping attitudes toward the welfare state. While the devout are expected to support pro-social values like helping others, and thus might be supportive of the welfare state, the possibility of taking action is undermined by the belief in God’s absolute control over world affairs and in a morally perfect providence, who is responsible for the fates of individuals. As the literature provides mixed results on this question, this study examines the role of belief in God’s control on welfare attitudes using three priming experiments and two priming tasks, carried out with a design that is both cross-cultural (US vs. Israel) and cross-religious tradition (Judaism vs. Catholicism). We find evidence that, largely, belief in God’s control increases support for income redistribution among Israeli Jews (study 1), American Jews (study 2), and American Catholics (study 3). The findings suggest that the traditional and common political gap between the economic left and the religious, based on the evaluation that religious beliefs lead to conservative economic preferences, may be overstated. PMID:26061050

  9. Advancing Leadership in Sport: Time to Take Off the Blinkers?

    PubMed

    Cruickshank, Andrew; Collins, Dave

    2016-09-01

    While leadership is one of the most significant factors in sport, most research has focused on who effective leaders are and what they overtly do rather than why and how they lead in a certain way at a certain time. Presumably shaped by social norms, the bulk of this work has also overstated the role of bright (or socially desirable) leadership intentions and behaviours; or at least overlooked how this style fits with the 'darker' (or socially undesirable) intentions and behaviours that are prevalent and effective in applied practice. Contextualising this situation against the origins and dominant paradigms of sport-specific study, we therefore highlight the need for greater emphasis on both the cognitive and dark sides of leadership. Regarding the former, we argue that expert leadership requires cognitive excellence given that optimal and consistent impact requires the conscious selection, combination and deployment of leadership behaviours. Regarding the latter, we also argue that bright intentions and behaviours can often only be a part of an effective leadership repertoire and can beneficially operate in tandem with inherently dark alternatives. To advance knowledge and practice, we therefore call for a more pragmatic approach to research that considers both the cognitive mechanisms-namely professional judgement and decision making-and the full spectrum of intentions and behaviours that underpin real world leadership.

  10. EPA’s Stage 2 Disinfection Byproducts Rules (DBPR) and Northern Kentucky Water: An Economic and Scientific Review

    PubMed Central

    Henry, Hugh

    2013-01-01

    Implementation of EPA’s Stage 2 Disinfection Byproducts Rules (DBPR) in Northern Kentucky will cause a water rate increase of over 25%. Hence a review was undertaken, considering both economics and science in the context of President Obama’s 2009 scientific integrity directive. The rules purport to avoid up to 0.49% of new bladder cancers by reducing the levels of DBPs in drinking water – a benefit so small that failure to implement will not cause unreasonable risk to health (URTH). It suggests at most one Northern Kentucky death avoided over 17 years for a cost of $136,000,000 ($1700 per household). Even this small benefit is probably overstated. EPA finds no “causal link” between DBPs and bladder cancer, and EPA acknowledges problems with the epidemiological data used in their calculation: the data appear contradictory and inconsistent, may be skewed toward “positive” results, and suggest different cancer sites than animal studies. Two similar international agencies disagree with EPA’s conclusions. The science is based on the Linear No Threshold (LNT) dose response model for DBPs, but this may not be the correct model. 83% of EPA’s epidemiological data show a statistical possibility that low levels of DBPs might be beneficial or have no effect. PMID:24298228

  11. EPA's Stage 2 Disinfection Byproducts Rules (DBPR) and Northern Kentucky Water: An Economic and Scientific Review.

    PubMed

    Henry, Hugh

    2013-01-01

    Implementation of EPA's Stage 2 Disinfection Byproducts Rules (DBPR) in Northern Kentucky will cause a water rate increase of over 25%. Hence a review was undertaken, considering both economics and science in the context of President Obama's 2009 scientific integrity directive. The rules purport to avoid up to 0.49% of new bladder cancers by reducing the levels of DBPs in drinking water - a benefit so small that failure to implement will not cause unreasonable risk to health (URTH). It suggests at most one Northern Kentucky death avoided over 17 years for a cost of $136,000,000 ($1700 per household). Even this small benefit is probably overstated. EPA finds no "causal link" between DBPs and bladder cancer, and EPA acknowledges problems with the epidemiological data used in their calculation: the data appear contradictory and inconsistent, may be skewed toward "positive" results, and suggest different cancer sites than animal studies. Two similar international agencies disagree with EPA's conclusions. The science is based on the Linear No Threshold (LNT) dose response model for DBPs, but this may not be the correct model. 83% of EPA's epidemiological data show a statistical possibility that low levels of DBPs might be beneficial or have no effect.

  12. Class in construction: London building workers, dirty work and physical cultures.

    PubMed

    Thiel, Darren

    2007-06-01

    Descriptions of manual employment tend to ignore its diversity and overstate the homogenizing effects of technology and industrialization. Based on ethnographic research on a London construction site, building work was found to be shaped by the forms of a pre-industrial work pattern characterized by task autonomy and freedom from managerial control. The builders' identities were largely free from personal identification as working class, and collective identification was fractured by trade status, and ethnic and gender divisions. Yet the shadow of a class-based discursive symbolism, which centered partly on the division of minds/bodies, mental/manual, and clean/dirty work, framed their accounts, identities and cultures. The builders displayed what is frequently termed working-class culture, and it was highly masculine. This physical and bodily-centered culture shielded them from the possible stigmatization of class and provided them with a source of localized capital. 'Physical capital' in conjunction with social capital (the builders' networks of friends and family) had largely guided their position in the stratification system, and values associated with these forms of capital were paramount to their public cultures. This cultural emphasis offered a continuing functionality in the builders' lives, not having broken free from tradition or becoming an object of reflexive choice.

  13. Validation of commercial business lists as a proxy for licensed alcohol outlets.

    PubMed

    Carlos, Heather A; Gabrielli, Joy; Sargent, James D

    2017-05-19

    Studies of retail alcohol outlets are restricted to regions due to lack of U.S. national data. Commercial business lists (BL) offer a possible solution, but no data exists to determine if BLs could serve as an adequate proxy for license data. This paper compares geospatial measures of alcohol outlets derived from a commercial BL with license data for a large US state. We validated BL data as a measure of off-premise alcohol outlet density and proximity compared to license data for 5528 randomly selected California residential addresses. We calculated three proximity measures (Euclidean distance, road network travel time and distance) and two density measures (kernel density estimation and the count within a 2-mile radius) for each dataset. The data was acquired in 2015 and processed and analyzed in 2015 and 2016. Correlations and reliabilities between density (correlation 0.98; Cronbach's α 0.97-0.99) and proximity (correlations 0.77-0.86; α 0.87-0.92) measures were high. For proximity, BL data matched license in 55-57% of addresses, overstated distance in 19%, and understated in 24-26%. BL data can serve as a reliable proxy for licensed alcohol outlets, thus extending the work that can be performed in studies on associations between retail alcohol outlets and drinking outcomes.

  14. A comparison of self-report and direct observation of booster seat use in Latino families.

    PubMed

    Quistberg, D Alex; Lozano, Paula; Mack, Christopher D; Schwartz, Rachel; Ebel, Beth E

    2010-08-01

    To develop a reliable self-report tool for measuring child booster seat use among Latino families. Cross-sectional and observational survey of a convenience sample. Five retail stores in King County, Washington. 50 parents of children 4-8 years old that self-identified as Latino or Hispanic. Parent-reported measures of how often the child uses a booster seat, if the child used a booster seat on the last trip, how often the child complains about using a booster seat, how often the child asks to not use a booster seat, and how often other families they know use a booster seat. Observed booster seat use by child. 26 children (52%) were observed using a booster seat. Parent-reported booster seat use was a poor predictor of observed booster seat use. Although 34 parents reported that their child 'always' uses a booster seat, 8 (24%) of these children were not using a booster seat. A logistic model to predict booster seat use had a sensitivity of 81% and a specificity of 71%, and misclassified 24% of the participants' observed use. Reliance on parent-reported booster seat use significantly overstated observed booster seat use in the study. Among this study population, accurate determination of booster seat use required direct observation.

  15. Sampling bias in climate-conflict research

    NASA Astrophysics Data System (ADS)

    Adams, Courtland; Ide, Tobias; Barnett, Jon; Detges, Adrien

    2018-03-01

    Critics have argued that the evidence of an association between climate change and conflict is flawed because the research relies on a dependent variable sampling strategy1-4. Similarly, it has been hypothesized that convenience of access biases the sample of cases studied (the `streetlight effect'5). This also gives rise to claims that the climate-conflict literature stigmatizes some places as being more `naturally' violent6-8. Yet there has been no proof of such sampling patterns. Here we test whether climate-conflict research is based on such a biased sample through a systematic review of the literature. We demonstrate that research on climate change and violent conflict suffers from a streetlight effect. Further, studies which focus on a small number of cases in particular are strongly informed by cases where there has been conflict, do not sample on the independent variables (climate impact or risk), and hence tend to find some association between these two variables. These biases mean that research on climate change and conflict primarily focuses on a few accessible regions, overstates the links between both phenomena and cannot explain peaceful outcomes from climate change. This could result in maladaptive responses in those places that are stigmatized as being inherently more prone to climate-induced violence.

  16. Buoyancy contribution to uncertainty of mass, conventional mass and force

    NASA Astrophysics Data System (ADS)

    Malengo, Andrea; Bich, Walter

    2016-04-01

    The conventional mass is a useful concept introduced to reduce the impact of the buoyancy correction in everyday mass measurements, thus avoiding in most cases its accurate determination, necessary in measurements of ‘true’ mass. Although usage of conventional mass is universal and standardized, the concept is considered as a sort of second-choice tool, to be avoided in high-accuracy applications. In this paper we show that this is a false belief, by elucidating the role played by covariances between volume and mass and between volume and conventional mass at the various stages of the dissemination chain and in the relationship between the uncertainties of mass and conventional mass. We arrive at somewhat counter-intuitive results: the volume of the transfer standard plays a comparatively minor role in the uncertainty budget of the standard under calibration. In addition, conventional mass is preferable to mass in normal, in-air operation, as its uncertainty is smaller than that of mass, if covariance terms are properly taken into account, and the uncertainty over-stating (typically) resulting from neglecting them is less severe than that (always) occurring with mass. The same considerations hold for force. In this respect, we show that the associated uncertainty is the same using mass or conventional mass, and, again, that the latter is preferable if covariance terms are neglected.

  17. Prevalence and socio-demographic correlates of time spent cooking by adults in the 2005 UK Time Use Survey. Cross-sectional analysis☆

    PubMed Central

    Adams, Jean; White, Martin

    2015-01-01

    This study aimed to document the prevalence and socio-demographic correlates of time spent cooking by adults in the 2005 UK Time-Use Survey. Respondents reported their main activities, in 10 minute slots, throughout one 24 hour period. Activities were coded into 30 pre-defined codes, including ‘cooking, washing up’. Four measures of time spent cooking were calculated: any time spent cooking, 30 continuous minutes spent cooking, total time spent cooking, and longest continuous time spent cooking. Socio-demographic correlates were: age, employment, social class, education, and number of adults and children in the household. Analyses were stratified by gender. Data from 4214 participants were included. 85% of women and 60% of men spent any time cooking; 60% of women and 33% of men spent 30 continuous minutes cooking. Amongst women, older age, not being in employment, lower social class, greater education, and living with other adults or children were positively associated with time cooking. Few differences in time spent cooking were seen in men. Socio-economic differences in time spent cooking may have been overstated as a determinant of socio-economic differences in diet, overweight and obesity. Gender was a stronger determinant of time spent cooking than other socio-demographic variables. PMID:26004671

  18. Estimating Surgical Procedure Times Using Anesthesia Billing Data and Operating Room Records.

    PubMed

    Burgette, Lane F; Mulcahy, Andrew W; Mehrotra, Ateev; Ruder, Teague; Wynn, Barbara O

    2017-02-01

    The median time required to perform a surgical procedure is important in determining payment under Medicare's physician fee schedule. Prior studies have demonstrated that the current methodology of using physician surveys to determine surgical times results in overstated times. To measure surgical times more accurately, we developed and validated a methodology using available data from anesthesia billing data and operating room (OR) records. We estimated surgical times using Medicare 2011 anesthesia claims and New York Statewide Planning and Research Cooperative System 2011 OR times. Estimated times were validated using data from the National Surgical Quality Improvement Program. We compared our time estimates to those used by Medicare in the fee schedule. We estimate surgical times via piecewise linear median regression models. Using 3.0 million observations of anesthesia and OR times, we estimated surgical time for 921 procedures. Correlation between these time estimates and directly measured surgical time from the validation database was 0.98. Our estimates of surgical time were shorter than the Medicare fee schedule estimates for 78 percent of procedures. Anesthesia and OR times can be used to measure surgical time and thereby improve the payment for surgical procedures in the Medicare fee schedule. © Health Research and Educational Trust.

  19. Quantifying errors without random sampling.

    PubMed

    Phillips, Carl V; LaPole, Luwanna M

    2003-06-12

    All quantifications of mortality, morbidity, and other health measures involve numerous sources of error. The routine quantification of random sampling error makes it easy to forget that other sources of error can and should be quantified. When a quantification does not involve sampling, error is almost never quantified and results are often reported in ways that dramatically overstate their precision. We argue that the precision implicit in typical reporting is problematic and sketch methods for quantifying the various sources of error, building up from simple examples that can be solved analytically to more complex cases. There are straightforward ways to partially quantify the uncertainty surrounding a parameter that is not characterized by random sampling, such as limiting reported significant figures. We present simple methods for doing such quantifications, and for incorporating them into calculations. More complicated methods become necessary when multiple sources of uncertainty must be combined. We demonstrate that Monte Carlo simulation, using available software, can estimate the uncertainty resulting from complicated calculations with many sources of uncertainty. We apply the method to the current estimate of the annual incidence of foodborne illness in the United States. Quantifying uncertainty from systematic errors is practical. Reporting this uncertainty would more honestly represent study results, help show the probability that estimated values fall within some critical range, and facilitate better targeting of further research.

  20. Modeling the economic outcomes of immuno-oncology drugs: alternative model frameworks to capture clinical outcomes.

    PubMed

    Gibson, E J; Begum, N; Koblbauer, I; Dranitsaris, G; Liew, D; McEwan, P; Tahami Monfared, A A; Yuan, Y; Juarez-Garcia, A; Tyas, D; Lees, M

    2018-01-01

    Economic models in oncology are commonly based on the three-state partitioned survival model (PSM) distinguishing between progression-free and progressive states. However, the heterogeneity of responses observed in immuno-oncology (I-O) suggests that new approaches may be appropriate to reflect disease dynamics meaningfully. This study explored the impact of incorporating immune-specific health states into economic models of I-O therapy. Two variants of the PSM and a Markov model were populated with data from one clinical trial in metastatic melanoma patients. Short-term modeled outcomes were benchmarked to the clinical trial data and a lifetime model horizon provided estimates of life years and quality adjusted life years (QALYs). The PSM-based models produced short-term outcomes closely matching the trial outcomes. Adding health states generated increased QALYs while providing a more granular representation of outcomes for decision making. The Markov model gave the greatest level of detail on outcomes but gave short-term results which diverged from those of the trial (overstating year 1 progression-free survival by around 60%). Increased sophistication in the representation of disease dynamics in economic models is desirable when attempting to model treatment response in I-O. However, the assumptions underlying different model structures and the availability of data for health state mapping may be important limiting factors.

  1. Sequential avulsions of the tibial tubercle in an adolescent basketball player.

    PubMed

    Huang, Ying Chieh; Chao, Ying-Hao; Lien, Fang-Chieh

    2010-05-01

    Tibial tubercle avulsion is an uncommon fracture in physically active adolescents. Sequential avulsion of tibial tubercles is extremely rare. We reported a healthy, active 15-year-old boy who suffered from left tibial tubercle avulsion fracture during a basketball game. He received open reduction and internal fixation with two smooth Kirschner wires and a cannulated screw, with every effort to reduce the plate injury. Long-leg splint was used for protection followed by programmed rehabilitation. He recovered uneventfully and returned to his previous level of activity soon. Another avulsion fracture happened at the right tibial tubercle 3.5 months later when he was playing the basketball. From the encouragement of previous successful treatment, we provided him open reduction and fixation with two small-caliber screws. He recovered uneventfully and returned to his previous level of activity soon. No genu recurvatum or other deformity was happening in our case at the end of 2-year follow-up. No evidence of Osgood-Schlatter disease or osteogenesis imperfecta was found. Sequential avulsion fractures of tibial tubercles are rare. Good functional recovery can often be obtained like our case if we treat it well. To a physically active adolescent, we should never overstate the risk of sequential avulsion of the other leg to postpone the return to an active, functional life.

  2. Colorectal cancer and 18FDG-PET/CT: What about adding the T to the N parameter in loco-regional staging?

    PubMed Central

    Mainenti, Pier Paolo; Iodice, Delfina; Segreto, Sabrina; Storto, Giovanni; Magliulo, Mario; Palma, Giovanni Domenico De; Salvatore, Marco; Pace, Leonardo

    2011-01-01

    AIM: To evaluate whether FDG-positron emission tomography (PET)/computed tomography (CT) may be an accurate technique in the assessment of the T stage in patients with colorectal cancer. METHODS: Thirty four consecutive patients (20 men and 14 women; mean age: 63 years) with a histologically proven diagnosis of colorectal adenocarcinoma and scheduled for surgery in our hospital were enrolled in this study. All patients underwent FDG-PET/CT preoperatively. The primary tumor site and extent were evaluated on PET/CT images. Colorectal wall invasion was analysed according to a modified T classification that considers only three stages (≤ T2, T3, T4). Assessment of accuracy was carried out using 95% confidence intervals for T. RESULTS: Thirty five/37 (94.6%) adenocarcinomas were identified and correctly located on PET/CT images. PET/CT correctly staged the T of 33/35 lesions identified showing an accuracy of 94.3% (95% CI: 87%-100%). All T1, T3 and T4 lesions were correctly staged, while two T2 neoplasms were overstated as T3. CONCLUSION: Our data suggest that FDG-PET/CT may be an accurate modality for identifying primary tumor and defining its local extent in patients with colorectal cancer. PMID:21472100

  3. Traceability validation of a high speed short-pulse testing method used in LED production

    NASA Astrophysics Data System (ADS)

    Revtova, Elena; Vuelban, Edgar Moreno; Zhao, Dongsheng; Brenkman, Jacques; Ulden, Henk

    2017-12-01

    Industrial processes of LED (light-emitting diode) production include LED light output performance testing. Most of them are monitored and controlled by optically, electrically and thermally measuring LEDs by high speed short-pulse measurement methods. However, these are not standardized and a lot of information is proprietary that it is impossible for third parties, such as NMIs, to trace and validate. It is known, that these techniques have traceability issue and metrological inadequacies. Often due to these, the claimed performance specifications of LEDs are overstated, which consequently results to manufacturers experiencing customers' dissatisfaction and a large percentage of failures in daily use of LEDs. In this research a traceable setup is developed to validate one of the high speed testing techniques, investigate inadequacies and work out the traceability issues. A well-characterised short square pulse of 25 ms is applied to chip-on-board (CoB) LED modules to investigate the light output and colour content. We conclude that the short-pulse method is very efficient in case a well-defined electrical current pulse is applied and the stabilization time of the device is "a priori" accurately determined. No colour shift is observed. The largest contributors to the measurement uncertainty include badly-defined current pulse and inaccurate calibration factor.

  4. Ethical implications of research on craving.

    PubMed

    Carter, Adrian; Hall, Wayne

    2013-02-01

    Cravings, intense desires to experience the effects of a drug, are widely regarded as significant impediments to overcoming addiction, although their role in relapse may be overstated. Scientists and clinicians wish to better understand the neurobiological and cognitive basis of craving so that they may develop psychotherapeutic, pharmacological and other medical methods to reduce craving and thereby drug use. The conduct of such research raises significant ethical issues. When recruiting individuals and conducting this research, scientists need to ensure that substance dependent participants have the capacity to provide free and uncoerced consent. This is especially the case in studies in which dependent participants are given their drug of addiction or provided with other inducements to participate (e.g. financial incentives) that may undermine their ability to fully consider the risks of participation. Treatments for addiction that seek to reduce cravings may also carry risks. This includes psychotherapeutic approaches, as well as pharmacological and medical treatments. Clinicians need to consider the risks and benefits of treatment and carefully communicate these to patients. The desire to reduce urges to use drugs should not be employed to justify potentially harmful and ineffective treatments. The safety and effectiveness of emerging treatments should be assessed by well conducted randomized controlled clinical trials. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. The impact of direct-to-consumer marketing of cancer genetic testing on women according to their genetic risk.

    PubMed

    Lowery, Jan T; Byers, Tim; Axell, Lisen; Ku, Lisa; Jacobellis, Jillian

    2008-12-01

    To assess the impact of direct-to-consumer marketing for genetic testing among women of varying genetic risk for breast and ovarian cancer. Telephone surveys were conducted with 315 women in Denver, Colorado, one target audience for the Myriad BRACAnalysis ad campaign. Genetic risk was determined from personal and family history and grouped by probability of having a BRCA1/2 mutation (low <5%, moderate 5-<10%, high > or =10%). High-risk women were more knowledgeable about BRACAnalysis and more likely to recall the media ads than were low-risk women (60 vs. 39%, P < 0.01). After seeing the ads, about 40% of women were more interested in testing and about 10% expressed increased worry about developing breast or ovarian cancer. Women across all risk groups overstated the benefits and appropriateness of testing. An equal percentage of high- and low-risk women (51 and 60%) felt that they would benefit from genetic testing. The campaign effectively reached a large audience. Concern about breast cancer was not appreciably increased. A large percentage of low-risk women (not candidates for testing) expressed interest in testing, suggesting the campaign was too broad. A campaign targeted at high-risk women, who may benefit from testing might be preferred.

  6. A new classification of spin in systematic reviews and meta-analyses was developed and ranked according to the severity.

    PubMed

    Yavchitz, Amélie; Ravaud, Philippe; Altman, Douglas G; Moher, David; Hrobjartsson, Asbjørn; Lasserson, Toby; Boutron, Isabelle

    2016-07-01

    We aimed to (1) identify and classify spin (i.e., a description that overstates efficacy and/or understates harm) in systematic reviews and (2) rank spin in abstracts of systematic reviews according to their severity (i.e., the likelihood of distorting readers' interpretation of the results). First, we used a four-phase consensus process to develop a classification of different types of spin. Second, we ranked the types of spin in abstracts according to their severity using a Q-sort survey with members of the Cochrane Collaboration. We identified 39 types of spin, 28 from the main text and 21 from the abstract; 13 were specific to the systematic review design. Spin was classified into three categories: (1) misleading reporting, (2) misleading interpretation, and (3) inappropriate extrapolation. Spin ranked as the most severe by the 122 people who participated in the survey were (1) recommendations for clinical practice not supported by findings in the conclusion, (2) misleading title, and (3) selective reporting. This study allowed for identifying spin that is likely to distort interpretation. Our classification could help authors, editors, and reviewers avoid spin in reports of systematic reviews. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Mexico's Luna discoveries are more than moonshine

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stewart-Gordon, T.J.; Baker, G.T.

    1987-05-01

    Just when it seemed that Mexico's petroleum reserves may have been overstated, the state oil company opened a new province. Petroleos Mexicanos (Pemex) geologists think the Luna area of Tabasco State and the Gulf of Mexico could add the condensate and gas equivalent of 20 billion bbl of light oil to Mexico's proven reserves. If true, this would be the largest discovery in Mexico since the Campeche Sound fields in 1976. To date, the new province stretches about 50 miles between the Caribbean coastal towns of Frontera and Puerto Ceiba in Tabasco State, and extends some 31 miles offshore (seemore » map). Since the early 1970s, Pemex geologists have postulated that the entire Yucatan platform will prove productive. Luna finds reduce the distance between Campeche fields and onshore production to 93 miles. The Luna area is ideally suited for rapid development - it is about 40 miles northeast of Villahermosa, Tabasco, and within 60 miles of the export terminal at Dos Bocas near the border between Tabasco and Vera Cruz states. It is also less than 50 miles from the Cactus gas-processing and petrochemical plants in Chiapas State, which means that gas can be put into the country's trunk line that extends to the U.S. grid at Reynosa.« less

  8. Lower-extremity musculoskeletal geometry affects the calculation of patellofemoral forces in vertical jumping and weightlifting.

    PubMed

    Cleather, D I; Bull, A M J

    2010-01-01

    The calculation of the patellofemoral joint contact force using three-dimensional (3D) modelling techniques requires a description of the musculoskeletal geometry of the lower limb. In this study, the influence of the complexity of the muscle model was studied by considering two different muscle models, the Delp and Horsman models. Both models were used to calculate the patellofemoral force during standing, vertical jumping, and Olympic-style weightlifting. The patellofemoral forces predicted by the Horsman model were markedly lower than those predicted by the Delp model in all activities and represented more realistic values when compared with previous work. This was found to be a result of a lower level of redundancy in the Delp model, which forced a higher level of muscular activation in order to allow a viable solution. The higher level of complexity in the Horsman model resulted in a greater degree of redundancy and consequently lower activation and patellofemoral forces. The results of this work demonstrate that a well-posed muscle model must have an adequate degree of complexity to create a sufficient independence, variability, and number of moment arms in order to ensure adequate redundancy of the force-sharing problem such that muscle forces are not overstated.

  9. Axisymmetric magnetorotational instability in ideal and viscous laboratory plasmas

    NASA Astrophysics Data System (ADS)

    Mikhailovskii, A. B.; Lominadze, J. G.; Churikov, A. P.; Erokhin, N. N.; Pustovitov, V. D.; Konovalov, S. V.

    2008-10-01

    The original analysis of the axisymmetric magnetorotational instability (MRI) by Velikhov (Sov. Phys. JETP 9, 995 (1959)) and Chandrasekhar (Proc. Nat. Acad. Sci. 46, 253 (1960)), applied to the ideally conducting magnetized medium in the laboratory conditions and restricted to the incompressible approximation, is extended by allowing for the compressibility. Thereby, two additional driving mechanisms of MRI are revealed in addition to the standard drive due to the negative medium rotation frequency gradient (the Velikhov effect). One is due to the squared medium pressure gradient and another is a combined effect of the pressure and density gradients. For laboratory applications, the expression for the MRI boundary with all the above driving mechanisms and the stabilizing magnetoacoustic effect is derived. The effects of parallel and perpendicular viscosities on the MRI in the laboratory plasma are investigated. It is shown that, for strong viscosity, there is a family of MRI driven for the same condition as the ideal one. It is also revealed that the presence of strong viscosity leads to additional family of instabilities called the viscosity-driven MRI. Then the parallel-viscositydriven MRI looks as an overstability (oscillatory instability) possessing both the growth rate and the real part of oscillation frequency, while the perpendicular-viscosity MRI is the aperiodical instability.

  10. Dynamic Multiple Work Stealing Strategy for Flexible Load Balancing

    NASA Astrophysics Data System (ADS)

    Adnan; Sato, Mitsuhisa

    Lazy-task creation is an efficient method of overcoming the overhead of the grain-size problem in parallel computing. Work stealing is an effective load balancing strategy for parallel computing. In this paper, we present dynamic work stealing strategies in a lazy-task creation technique for efficient fine-grain task scheduling. The basic idea is to control load balancing granularity depending on the number of task parents in a stack. The dynamic-length strategy of work stealing uses run-time information, which is information on the load of the victim, to determine the number of tasks that a thief is allowed to steal. We compare it with the bottommost first work stealing strategy used in StackThread/MP, and the fixed-length strategy of work stealing, where a thief requests to steal a fixed number of tasks, as well as other multithreaded frameworks such as Cilk and OpenMP task implementations. The experiments show that the dynamic-length strategy of work stealing performs well in irregular workloads such as in UTS benchmarks, as well as in regular workloads such as Fibonacci, Strassen's matrix multiplication, FFT, and Sparse-LU factorization. The dynamic-length strategy works better than the fixed-length strategy because it is more flexible than the latter; this strategy can avoid load imbalance due to overstealing.

  11. Pharmacological treatment of cardiac glycoside poisoning.

    PubMed

    Roberts, Darren M; Gallapatthy, Gamini; Dunuwille, Asunga; Chan, Betty S

    2016-03-01

    Cardiac glycosides are an important cause of poisoning, reflecting their widespread clinical usage and presence in natural sources. Poisoning can manifest as varying degrees of toxicity. Predominant clinical features include gastrointestinal signs, bradycardia and heart block. Death occurs from ventricular fibrillation or tachycardia. A wide range of treatments have been used, the more common including activated charcoal, atropine, β-adrenoceptor agonists, temporary pacing, anti-digoxin Fab and magnesium, and more novel agents include fructose-1,6-diphosphate (clinical trial in progress) and anticalin. However, even in the case of those treatments that have been in use for decades, there is debate regarding their efficacy, the indications and dosage that optimizes outcomes. This contributes to variability in use across the world. Another factor influencing usage is access. Barriers to access include the requirement for transfer to a specialized centre (for example, to receive temporary pacing) or financial resources (for example, anti-digoxin Fab in resource poor countries). Recent data suggest that existing methods for calculating the dose of anti-digoxin Fab in digoxin poisoning overstate the dose required, and that its efficacy may be minimal in patients with chronic digoxin poisoning. Cheaper and effective medicines are required, in particular for the treatment of yellow oleander poisoning which is problematic in resource poor countries. © 2015 The British Pharmacological Society.

  12. Current perspectives and the future of domestication studies

    PubMed Central

    Larson, Greger; Piperno, Dolores R.; Allaby, Robin G.; Purugganan, Michael D.; Andersson, Leif; Arroyo-Kalin, Manuel; Barton, Loukas; Climer Vigueira, Cynthia; Denham, Tim; Dobney, Keith; Doust, Andrew N.; Gepts, Paul; Gilbert, M. Thomas P.; Gremillion, Kristen J.; Lucas, Leilani; Lukens, Lewis; Marshall, Fiona B.; Olsen, Kenneth M.; Pires, J. Chris; Richerson, Peter J.; Rubio de Casas, Rafael; Sanjur, Oris I.; Thomas, Mark G.; Fuller, Dorian Q.

    2014-01-01

    It is difficult to overstate the cultural and biological impacts that the domestication of plants and animals has had on our species. Fundamental questions regarding where, when, and how many times domestication took place have been of primary interest within a wide range of academic disciplines. Within the last two decades, the advent of new archaeological and genetic techniques has revolutionized our understanding of the pattern and process of domestication and agricultural origins that led to our modern way of life. In the spring of 2011, 25 scholars with a central interest in domestication representing the fields of genetics, archaeobotany, zooarchaeology, geoarchaeology, and archaeology met at the National Evolutionary Synthesis Center to discuss recent domestication research progress and identify challenges for the future. In this introduction to the resulting Special Feature, we present the state of the art in the field by discussing what is known about the spatial and temporal patterns of domestication, and controversies surrounding the speed, intentionality, and evolutionary aspects of the domestication process. We then highlight three key challenges for future research. We conclude by arguing that although recent progress has been impressive, the next decade will yield even more substantial insights not only into how domestication took place, but also when and where it did, and where and why it did not. PMID:24757054

  13. The carbon footprint of traditional woodfuels

    NASA Astrophysics Data System (ADS)

    Bailis, Robert; Drigo, Rudi; Ghilardi, Adrian; Masera, Omar

    2015-03-01

    Over half of all wood harvested worldwide is used as fuel, supplying ~9% of global primary energy. By depleting stocks of woody biomass, unsustainable harvesting can contribute to forest degradation, deforestation and climate change. However, past efforts to quantify woodfuel sustainability failed to provide credible results. We present a spatially explicit assessment of pan-tropical woodfuel supply and demand, calculate the degree to which woodfuel demand exceeds regrowth, and estimate woodfuel-related greenhouse-gas emissions for the year 2009. We estimate 27-34% of woodfuel harvested was unsustainable, with large geographic variations. Our estimates are lower than estimates from carbon offset projects, which are probably overstating the climate benefits of improved stoves. Approximately 275 million people live in woodfuel depletion `hotspots’--concentrated in South Asia and East Africa--where most demand is unsustainable. Emissions from woodfuels are 1.0-1.2 Gt CO2e yr-1 (1.9-2.3% of global emissions). Successful deployment and utilization of 100 million improved stoves could reduce this by 11-17%. At US$11 per tCO2e, these reductions would be worth over US$1 billion yr-1 in avoided greenhouse-gas emissions if black carbon were integrated into carbon markets. By identifying potential areas of woodfuel-driven degradation or deforestation, we inform the ongoing discussion about REDD-based approaches to climate change mitigation.

  14. Le Fort-based maxillofacial transplantation: current state of the art and a refined technique using orthognathic applications.

    PubMed

    Gordon, Chad R; Susarla, Srinivas M; Peacock, Zachary S; Kaban, Leonard B; Yaremchuk, Michael J

    2012-01-01

    Following encouraging results from the first 6 maxillofacial allotransplants, there has been a dramatic rise in interest worldwide. Numerous groups are now devoting resources to increase the frequency of these complex procedures, and with this, the craniomaxillofacial surgeon should become familiar with the emerging state of the art. This article reviews the evolution of Le Fort-based cadaveric studies pertaining to maxillofacial allotransplantation, briefly describes the clinical reports through 2010, and introduces a refined technique applying orthognathic applications. Preliminary studies over the last 5 years have highlighted the challenges associated with transplanting skeletal components, and clinical results presented thus far have been extremely promising. However, a notable area for improvement is suboptimal facial-skeletal harmony and profile in the context of sagittal skeletal projection and maxillomandibular relation. To our knowledge, orthognathic planning as applied to osteocutaneous face transplantation has not been described. Many recipients seen thus far demonstrate some degree of malocclusion and suboptimal harmony, as expected, given the donor-to-recipient skeletal/jaw discrepancies. Given that the goal is to improve function as well as form, the importance of orthognathic planning cannot be overstated with respect to optimizing harmony, profile, and occlusion. Preoperative planning, including generation of donor/recipient dental cast models, as described herein for the first time, is essential.

  15. Design Considerations in Capacitively Coupled Plasmas

    NASA Astrophysics Data System (ADS)

    Song, Sang-Heon; Ventzek, Peter; Ranjan, Alok

    2015-11-01

    Microelectronics industry has driven transistor feature size scaling from 10-6 m to 10-9 m during the past 50 years, which is often referred to as Moore's law. It cannot be overstated that today's information technology would not have been so successful without plasma material processing. One of the major plasma sources for the microelectronics fabrication is capacitively coupled plasmas (CCPs). The CCP reactor has been intensively studied and developed for the deposition and etching of different films on the silicon wafer. As the feature size gets to around 10 nm, the requirement for the process uniformity is less than 1-2 nm across the wafer (300 mm). In order to achieve the desired uniformity, the hardware design should be as precise as possible before the fine tuning of process condition is applied to make it even better. In doing this procedure, the computer simulation can save a significant amount of resources such as time and money which are critical in the semiconductor business. In this presentation, we compare plasma properties using a 2-dimensional plasma hydrodynamics model for different kinds of design factors that can affect the plasma uniformity. The parameters studied in this presentation include chamber accessing port, pumping port, focus ring around wafer substrate, and the geometry of electrodes of CCP.

  16. Criticisms biologically unwarranted and analytically irrelevant: Reply to Rominger et al.

    USGS Publications Warehouse

    Bender, L.C.; Weisenberger, M.E.

    2009-01-01

    The criticisms of Rominger et al. (2008) of our retrospective analysis of desert bighorn sheep (DBS; Ovis canadensis mexicana) dynamics in the San Andres Mountains of south-central New Mexico, USA, contained many biological errors and analytical oversights. Herein, we show that Rominger et al. (2008) 1) overstated both magnitude and potential effect of predator removal; 2) incorrectly claimed that our total precipitation (TP) model did not fit the data when TP correctly classed ???66 of subsequent population increases and declines (P ??? 0.063); 3) presented a necessary prerequisite of the exponential model (serial correlation between Nt and Nt1) as the key relationship in the DBS data, when it merely reflected that DBS are strongly K-selected and was irrelevant to our hypothesis tests specific to factors affecting the instantaneous rate of population increase (r); 4) greatly oversimplified relationships among precipitation, arid environments, and DBS; and 5) advocated a time for collection of lamb/female (L/F) ratio data that was unrelated to any meaningful period in the biological year of DBS and consequently presented L/F ratio data unrelated to observed dynamics of DBS. In contrast, the L/F ratios used in Bender and Weisenberger (2005) correctly predicted annual changes and were correlated with long-term population rates of change.

  17. On the study of plant defence and herbivory using comparative approaches: how important are secondary plant compounds.

    PubMed

    Agrawal, Anurag A; Weber, Marjorie G

    2015-10-01

    Species comparisons are a cornerstone of biology and there is a long tradition of using the comparative framework to study the ecology and evolution of plant defensive traits. Early comparative studies led to the hypothesis that plant chemistry plays a central role in plant defence, and the evolution of plant secondary chemistry in response to insect herbivory remains a classic example of coevolution. However, recent comparative work has disagreed with this paradigm, reporting little connection between plant secondary chemicals and herbivory across distantly related plant taxa. One conclusion of this new work is that the importance of secondary chemistry in plant defence may have been generally overstated in earlier research. Here, we attempt to reconcile these contradicting viewpoints on the role of plant chemistry in defence by critically evaluating the use and interpretation of species correlations as a means to study defence-herbivory relationships. We conclude that the notion that plant primary metabolites (e.g. leaf nitrogen content) are the principal determinants of herbivory (or the target of natural selection by herbivores) is not likely to be correct. Despite the inference of recent community-wide studies of herbivory, strong evidence remains for a prime role of secondary compounds in plant defence against herbivores. © 2015 John Wiley & Sons Ltd/CNRS.

  18. The niche construction perspective: a critical appraisal.

    PubMed

    Scott-Phillips, Thomas C; Laland, Kevin N; Shuker, David M; Dickins, Thomas E; West, Stuart A

    2014-05-01

    Niche construction refers to the activities of organisms that bring about changes in their environments, many of which are evolutionarily and ecologically consequential. Advocates of niche construction theory (NCT) believe that standard evolutionary theory fails to recognize the full importance of niche construction, and consequently propose a novel view of evolution, in which niche construction and its legacy over time (ecological inheritance) are described as evolutionary processes, equivalent in importance to natural selection. Here, we subject NCT to critical evaluation, in the form of a collaboration between one prominent advocate of NCT, and a team of skeptics. We discuss whether niche construction is an evolutionary process, whether NCT obscures or clarifies how natural selection leads to organismal adaptation, and whether niche construction and natural selection are of equivalent explanatory importance. We also consider whether the literature that promotes NCT overstates the significance of niche construction, whether it is internally coherent, and whether it accurately portrays standard evolutionary theory. Our disagreements reflect a wider dispute within evolutionary theory over whether the neo-Darwinian synthesis is in need of reformulation, as well as different usages of some key terms (e.g., evolutionary process). © 2013 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.

  19. Scenarios for coastal vulnerability assessment

    USGS Publications Warehouse

    Nicholls, Robert J.; Woodroffe, Colin D.; Burkett, Virginia; Hay, John; Wong, Poh Poh; Nurse, Leonard; Wolanski, Eric; McLusky, Donald S.

    2011-01-01

    Coastal vulnerability assessments tend to focus mainly on climate change and especially on sea-level rise. Assessment of the influence of nonclimatic environmental change or socioeconomic change is less well developed and these drivers are often completely ignored. Given that the most profound coastal changes of the twentieth century due to nonclimate drivers are likely to continue through the twenty-first century, this is a major omission. It may result in not only overstating the importance of climate change but also overlooking significant interactions of climate change and other drivers. To support the development of policies relating to climate change and coastal management, integrated assessments of climatic change in coastal areas are required, including the effects of all the relevant drivers. This chapter explores the development of scenarios (or "plausible futures") of relevant climate and nonclimate drivers that can be used for coastal analysis, with an emphasis on the nonclimate drivers. It shows the importance of analyzing the impacts of climate change and sea-level rise in a broader context of coastal change and all its drivers. This will improve the analysis of impacts, key vulnerabilities, and adaptation needs and, hence, inform climate and coastal policy. Stakeholder engagement is important in the development of scenarios, and the underlying assumptions need to be explicit, transparent, and open to scientific debate concerning their uncertainties/realism and likelihood.

  20. When physics is not "just physics": complexity science invites new measurement frames for exploring the physics of cognitive and biological development.

    PubMed

    Kelty-Stephen, Damian; Dixon, James A

    2012-01-01

    The neurobiological sciences have struggled to resolve the physical foundations for biological and cognitive phenomena with a suspicion that biological and cognitive systems, capable of exhibiting and contributing to structure within themselves and through their contexts, are fundamentally distinct or autonomous from purely physical systems. Complexity science offers new physics-based approaches to explaining biological and cognitive phenomena. In response to controversy over whether complexity science might seek to "explain away" biology and cognition as "just physics," we propose that complexity science serves as an application of recent advances in physics to phenomena in biology and cognition without reducing or undermining the integrity of the phenomena to be explained. We highlight that physics is, like the neurobiological sciences, an evolving field and that the threat of reduction is overstated. We propose that distinctions between biological and cognitive systems from physical systems are pretheoretical and thus optional. We review our own work applying insights from post-classical physics regarding turbulence and fractal fluctuations to the problems of developing cognitive structure. Far from hoping to reduce biology and cognition to "nothing but" physics, we present our view that complexity science offers new explanatory frameworks for considering physical foundations of biological and cognitive phenomena.

  1. Climate change and coastal vulnerability assessment: Scenarios for integrated assessment

    USGS Publications Warehouse

    Nicholls, R.J.; Wong, P.P.; Burkett, V.; Woodroffe, C.D.; Hay, J.

    2008-01-01

    Coastal vulnerability assessments still focus mainly on sea-level rise, with less attention paid to other dimensions of climate change. The influence of non-climatic environmental change or socio-economic change is even less considered, and is often completely ignored. Given that the profound coastal changes of the twentieth century are likely to continue through the twenty-first century, this is a major omission, which may overstate the importance of climate change, and may also miss significant interactions of climate change with other non-climate drivers. To better support climate and coastal management policy development, more integrated assessments of climatic change in coastal areas are required, including the significant non-climatic changes. This paper explores the development of relevant climate and non-climate drivers, with an emphasis on the non-climate drivers. While these issues are applicable within any scenario framework, our ideas are illustrated using the widely used SRES scenarios, with both impacts and adaptation being considered. Importantly, scenario development is a process, and the assumptions that are made about future conditions concerning the coast need to be explicit, transparent and open to scientific debate concerning their realism and likelihood. These issues are generic across other sectors. ?? Integrated Research System for Sustainability Science and Springer 2008.

  2. Historical effects of CO2 and climate trends on global crop water demand

    NASA Astrophysics Data System (ADS)

    Urban, Daniel W.; Sheffield, Justin; Lobell, David B.

    2017-12-01

    A critical question for agricultural production and food security is how water demand for staple crops will respond to climate and carbon dioxide (CO2) changes1, especially in light of the expected increases in extreme heat exposure2. To quantify the trade-offs between the effects of climate and CO2 on water demand, we use a `sink-strength' model of demand3,4 which relies on the vapour-pressure deficit (VPD), incident radiation and the efficiencies of canopy-radiation use and canopy transpiration; the latter two are both dependent on CO2. This model is applied to a global data set of gridded monthly weather data over the cropping regions of maize, soybean, wheat and rice during the years 1948-2013. We find that this approach agrees well with Penman-Monteith potential evapotranspiration (PM) for the C3 crops of soybean, wheat and rice, where the competing CO2 effects largely cancel each other out, but that water demand in maize is significantly overstated by a demand measure that does not include CO2, such as the PM. We find the largest changes in wheat, for which water demand has increased since 1981 over 86% of the global cropping area and by 2.3-3.6 percentage points per decade in different regions.

  3. Comparing the content of leadership theories and managers' shared perceptions of effective leadership: a Q-method study of trainee managers in the English NHS.

    PubMed

    Freeman, Tim

    2013-08-01

    Health service managers face potential conflicts between corporate and professional agendas, a tension sharpened for trainees by their junior status and relative inexperience. While academic leadership theory forms an integral part of contemporary management development programmes, relatively little is known of trainees' patterned subjectivities in relation to leadership theories. The objective of this study was to explore such subjectivities within a cohort of trainees on the National Health Service Graduate Management Training Scheme (NHS GMTS), a 'fast-track' programme which prepares graduate entrants for director-level health service management posts. A Q-method design was used and four shared subjectivities were identified: leadership as collaborative social process ('relational'); leadership as integrity ('moral'); leadership as effective support of subordinates ('team'); and leadership as construction of a credible leadership persona ('identity'). While the factors broadly map onto competencies indicated within the NHS Leadership Qualities Framework which underpin assessments of performance for this student group, it is important not to overstate the governance effect of the assessment regime. Rather, factors reflect tensions between required competencies, namely the mobilisation of diverse interest groups, the ethical base of decisions and the identity work required to convince others of leadership status. Indeed, factor 2 ('moral') effectively defines leadership as the embodiment of public service ethos. © The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  4. Arrogance analysis of several typical pattern recognition classifiers

    NASA Astrophysics Data System (ADS)

    Jing, Chen; Xia, Shengping; Hu, Weidong

    2007-04-01

    Various kinds of classification methods have been developed. However, most of these classical methods, such as Back-Propagation (BP), Bayesian method, Support Vector Machine(SVM), Self-Organizing Map (SOM) are arrogant. A so-called arrogance, for a human, means that his decision, which even is a mistake, overstates his actual experience. Accordingly, we say that he is a arrogant if he frequently makes arrogant decisions. Likewise, some classical pattern classifiers represent the similar characteristic of arrogance. Given an input feature vector, we say a classifier is arrogant in its classification if its veracity is high yet its experience is low. Typically, for a new sample which is distinguishable from original training samples, traditional classifiers recognize it as one of the known targets. Clearly, arrogance in classification is an undesirable attribute. Conversely, a classifier is non-arrogant in its classification if there is a reasonable balance between its veracity and its experience. Inquisitiveness is, in many ways, the opposite of arrogance. In nature, inquisitiveness is an eagerness for knowledge characterized by the drive to question, to seek a deeper understanding. The human capacity to doubt present beliefs allows us to acquire new experiences and to learn from our mistakes. Within the discrete world of computers, inquisitive pattern recognition is the constructive investigation and exploitation of conflict in information. Thus, we quantify this balance and discuss new techniques that will detect arrogance in a classifier.

  5. Consistency of Use and Effectiveness of Household Water Treatment Practices among Urban and Rural Populations Claiming to Treat Their Drinking Water at Home: A Case Study in Zambia

    PubMed Central

    Rosa, Ghislaine; Kelly, Paul; Clasen, Thomas

    2016-01-01

    Household water treatment (HWT) can improve drinking water quality and prevent disease, if used correctly and consistently. While international monitoring suggests that 1.8 billion people practice HWT, these estimates are based on household surveys that may overstate the level of consistent use and do not address microbiological effectiveness. We sought to examine how HWT is practiced among households identified as HWT users according to international monitoring standards. Case studies were conducted in urban and rural Zambia. After a baseline survey (urban: 203 households, rural: 276 households) to identify HWT users, 95 urban and 82 rural households were followed up for 6 weeks. Consistency of HWT reporting was low; only 72.6% of urban and 50.0% of rural households reported to be HWT users in the subsequent visit. Similarly, availability of treated water was low, only 23.3% and 4.2% of urban and rural households, respectively, had treated water on all visits. Drinking water was significantly worse than source water in both settings. Only 19.6% of urban and 2.4% of rural households had drinking water free of thermotolerant coliforms on all visits. Our findings raise questions about the value of the data gathered through the international monitoring of HWT practices as predictors of water quality in the home. PMID:26572868

  6. Injury prophylaxis in paragliding

    PubMed Central

    Schulze, W; Richter, J; Schulze, B; Esenwein, S; Buttner-Janz, K

    2002-01-01

    Objectives: To show trends in paragliding injuries and derive recommendations for safety precautions for paraglider pilots on the basis of accident statistics, interviews, questionnaires, medical reports, and current stage of development of paragliding equipment. Methods: All paragliding accidents in Germany have to be reported. Information on 409 accidents was collected and analysed for the period 1997–1999. Results: There was a substantial decrease in reported accidents (166 in 1997; 127 in 1998; 116 in 1999). The number of accidents resulting in spinal injuries was 62 in 1997, 42 in 1998, and 38 in 1999. The most common cause of accident was deflation of the glider (32.5%), followed by oversteering (13.9%), collision with obstacles (12.0%), take off errors (10.3%), landing errors (13.7%), misjudgment of weather conditions (4.9%), unsatisfactory preflight checks (4.9%), mid-air collisions with other flyers (2.2%), accidents during winching (2.2%), and defective equipment (0.5%). Accidents predominantly occurred in mountain areas. Fewer than 100 flights had been logged for 40% of injured pilots. In a total of 39 accidents in which emergency parachutes were used, 10 pilots were seriously injured (26%) and an additional three were killed (8%). Conclusions: Injuries in paragliding caused by unpredictable situations can be minimised by (a) using safer gliders in the beginner or intermediate category, (b) improving protection systems, such as padded back protection, and (c) improving pilot skills through performance and safety training. PMID:12351336

  7. Modeling the economic outcomes of immuno-oncology drugs: alternative model frameworks to capture clinical outcomes

    PubMed Central

    Gibson, EJ; Begum, N; Koblbauer, I; Dranitsaris, G; Liew, D; McEwan, P; Tahami Monfared, AA; Yuan, Y; Juarez-Garcia, A; Tyas, D; Lees, M

    2018-01-01

    Background Economic models in oncology are commonly based on the three-state partitioned survival model (PSM) distinguishing between progression-free and progressive states. However, the heterogeneity of responses observed in immuno-oncology (I-O) suggests that new approaches may be appropriate to reflect disease dynamics meaningfully. Materials and methods This study explored the impact of incorporating immune-specific health states into economic models of I-O therapy. Two variants of the PSM and a Markov model were populated with data from one clinical trial in metastatic melanoma patients. Short-term modeled outcomes were benchmarked to the clinical trial data and a lifetime model horizon provided estimates of life years and quality adjusted life years (QALYs). Results The PSM-based models produced short-term outcomes closely matching the trial outcomes. Adding health states generated increased QALYs while providing a more granular representation of outcomes for decision making. The Markov model gave the greatest level of detail on outcomes but gave short-term results which diverged from those of the trial (overstating year 1 progression-free survival by around 60%). Conclusion Increased sophistication in the representation of disease dynamics in economic models is desirable when attempting to model treatment response in I-O. However, the assumptions underlying different model structures and the availability of data for health state mapping may be important limiting factors. PMID:29563820

  8. Recommendations for gross examination and sampling of surgical specimens of the spleen.

    PubMed

    O'Malley, Dennis P; Louissaint, Abner; Vasef, Mohammad A; Auerbach, Aaron; Miranda, Roberto; Brynes, Russell K; Fedoriw, Yuri; Hudnall, S David

    2015-10-01

    This review examines handling and processing of spleen biopsies and splenectomy specimens with the aim of providing the pathologist with guidance in optimizing examination and diagnosis of splenic disorders. It also offers recommendations as to relevant reporting factors in gross examination, which may guide diagnostic workup. The role of splenic needle biopsies is discussed. The International Spleen Consortium is a group dedicated to promoting education and research on the anatomy, physiology, and pathology of the spleen. In keeping with these goals, we have undertaken to provide guidelines for gross examination, sectioning, and sampling of spleen tissue to optimize diagnosis (Burke). The pathology of the spleen may be complicated in routine practice due to a number of factors. Among these are lack of familiarity with lesions, complex histopathology, mimicry within several types of lesions, and overall rarity. To optimize diagnosis, appropriate handling and processing of splenic tissue are crucial. The importance of complete and accurate clinical history cannot be overstated. In many cases, significant clinical history such as previous lymphoproliferative disorders, hematologic disorders, trauma, etc, can provide important information to guide the evaluation of spleen specimens. Clinical information helps plan for appropriate processing of the spleen specimen. The pathologist should encourage surgical colleagues, who typically provide the specimens, to include as much clinical information as possible. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Bayesian probabilistic population projections for all countries.

    PubMed

    Raftery, Adrian E; Li, Nan; Ševčíková, Hana; Gerland, Patrick; Heilig, Gerhard K

    2012-08-28

    Projections of countries' future populations, broken down by age and sex, are widely used for planning and research. They are mostly done deterministically, but there is a widespread need for probabilistic projections. We propose a bayesian method for probabilistic population projections for all countries. The total fertility rate and female and male life expectancies at birth are projected probabilistically using bayesian hierarchical models estimated via Markov chain Monte Carlo using United Nations population data for all countries. These are then converted to age-specific rates and combined with a cohort component projection model. This yields probabilistic projections of any population quantity of interest. The method is illustrated for five countries of different demographic stages, continents and sizes. The method is validated by an out of sample experiment in which data from 1950-1990 are used for estimation, and applied to predict 1990-2010. The method appears reasonably accurate and well calibrated for this period. The results suggest that the current United Nations high and low variants greatly underestimate uncertainty about the number of oldest old from about 2050 and that they underestimate uncertainty for high fertility countries and overstate uncertainty for countries that have completed the demographic transition and whose fertility has started to recover towards replacement level, mostly in Europe. The results also indicate that the potential support ratio (persons aged 20-64 per person aged 65+) will almost certainly decline dramatically in most countries over the coming decades.

  10. Prognostic significance of anaplasia and angiogenesis in childhood medulloblastoma: a pediatric oncology group study.

    PubMed

    Ozer, Erdener; Sarialioglu, Faik; Cetingoz, Riza; Yüceer, Nurullah; Cakmakci, Handan; Ozkal, Sermin; Olgun, Nur; Uysal, Kamer; Corapcioglu, Funda; Canda, Serefettin

    2004-01-01

    The purpose of this study was to investigate whether quantitative assessment of cytologic anaplasia and angiogenesis may predict the clinical prognosis in medulloblastoma and stratify the patients to avoid both undertreatment and overtreatment. Medulloblastomas from 23 patients belonging to the Pediatric Oncology Group were evaluated with respect to some prognostic variables, including histologic assessment of nodularity and desmoplasia, grading of anaplasia, measurement of nuclear size, mitotic cell count, quantification of angiogenesis, including vascular surface density (VSD) and microvessel number (NVES), and immunohistochemical scoring of vascular endothelial growth factor (VEGF) expression. Univariate and multivariate analyses for prognostic indicators for survival were performed. Univariate analysis revealed that extensive nodularity was a significant favorable prognostic factor, whereas the presence of anaplasia, increased nuclear size, mitotic rate, VSD, and NVES were significant unfavorable prognostic factors. Using multivariate analysis, increased nuclear size was found to be an independent unfavorable prognostic factor for survival. Neither the presence of desmoplasia nor VEGF expression was significantly related to patient survival. Although care must be taken not to overstate the importance of the results of this single-institution preliminary report, pathologic grading of medulloblastomas with respect to grading of anaplasia and quantification of nodularity, nuclear size, and microvessel profiles may be clinically useful for the treatment of medulloblastomas. Further validation of the independent prognostic significance of nuclear size in stratifying patients is required.

  11. Further results on the macroeconomic effects of AIDS: the dualistic, labor-surplus economy.

    PubMed

    Cuddington, J T

    1993-09-01

    Analyses by Cuddington in 1993 and forthcoming work from Cuddington and Hancock model the macroeconomic effects of the AIDS epidemic using a modified Solow growth model. This single-sector framework rests upon the assumption that labor and capital are always efficiently allocated throughout the economy with neither market failures nor policy-induced distortions resulting in resource misallocation. Economies in low-income developing countries in sub-Saharan Africa, however, are not operating at capacity. Impact models based upon the potential growth path of economies will therefore significantly overstate the effect of an AIDS epidemic. The author thus incorporates the presence of underemployment and dual labor markets to redress the limitations of these earlier impact models. The dual-economy simulations of the economic impact of AIDS using Tanzanian data suggest that the macroeconomic consequences of the epidemic are of the same order of magnitude as those obtained using a single-sector, full-employment model: gross domestic product (GDP) is 15-25% smaller by 2010 than it would have been without AIDS, and per capita GDP is 0-10% smaller. Output lost from AIDS in the dual-economy framework is approximately the same as the output gain achievable through policies designed to increase labor market flexibility. Findings suggest that serious economic reform in economies fraught with AIDS may lessen the negative economic effects of the epidemic.

  12. Women recovering from first-time myocardial infarction (MI): a feminist qualitative study.

    PubMed

    Jackson, D; Daly, J; Davidson, P; Elliott, D; Cameron-Traub, E; Wade, V; Chin, C; Salamonson, Y

    2000-12-01

    Although myocardial infarction (MI) is a leading cause of death and disablement for women internationally, little is known about women's recovery. This paper describes an exploratory descriptive study that was informed by feminist principles, and which aimed to explore the recovery experiences of a group of women survivors of first-time MI in the initial period following discharge from hospital. A total of 10 female survivors were interviewed using an open-ended semi-structured interview schedule administered at 7, 14 and 21 days post-hospital discharge. Findings revealed that recovery was experienced as a complex process, initially characterized by fear and uncertainty. Over the duration of the study these feelings were replaced with a more positive outlook, a return of energy, and a sense of confidence in the future. Participants identified an unmet need for reliable information which persisted over the duration of the study. The findings of this study have implications for nursing practice and research. Chief among these is the issue of effective provision of information to women following an acute MI. The importance of providing relevant information to be understood and retained by people experiencing crisis cannot be overstated. Equally important are the provision of opportunities for patients to have regular contact with health professionals to question and seek clarifying information. These findings should now be tested on larger populations.

  13. Stellar Occultations by Saturn's Rings

    NASA Astrophysics Data System (ADS)

    Nicholson, Philip; Hedman, Matthew; French, Richard G.; Ansty, Todd

    2018-04-01

    On 15 September 2017 the Cassini mission came to an end when the spacecraft made a controlled entry into the planet's atmosphere. Over the preceding 13 years the Visual and Infrared Mapping Spectrometer (VIMS) instrument successfully observed over 170 stellar occultations by Saturn's rings, greatly increasing the available data set for high-resolution studies of the rings' structure and dynamics. Ring opening angles, B_\\ast ranged from 1.06° to 74.18°, while spacecraft ranges varied from 220,000 to 3,014,000 km. The effective radial resolution of the data is determined by a combination of Fresnel diffraction, stellar diameter and sampling rate, but is typically 150-300~m. We will briefly review the overall data set, before looking at examples of dynamical studies carried out with it over the past decade. These include modeling the geometry of self-gravity wakes in the A and B rings, evidence for viscous over-stability in the inner A ring, studies of eccentric, inclined and more complex orbital perturbations on the edges of isolated ringlets and narrow gaps, identification of density and bending waves in the C ring driven by both internal oscillations and gravity anomalies in Saturn, and the first reliable estimates of surface mass density in the central B ring.{\\bf References:} French \\etal\\ (2016a, 2016b, 2017), Hedman \\etal\\ (2007, 2010, 2014), Hedman \\& Nicholson (2013, 2014, 2016), Nicholson \\& Hedman (2010, 2016), Nicholson \\etal\\ (2014a, 2014b).

  14. An introduction to optical super-resolution microscopy for the adventurous biologist

    NASA Astrophysics Data System (ADS)

    Vangindertael, J.; Camacho, R.; Sempels, W.; Mizuno, H.; Dedecker, P.; Janssen, K. P. F.

    2018-04-01

    Ever since the inception of light microscopy, the laws of physics have seemingly thwarted every attempt to visualize the processes of life at its most fundamental, sub-cellular, level. The diffraction limit has restricted our view to length scales well above 250 nm and in doing so, severely compromised our ability to gain true insights into many biological systems. Fortunately, continuous advancements in optics, electronics and mathematics have since provided the means to once again make physics work to our advantage. Even though some of the fundamental concepts enabling super-resolution light microscopy have been known for quite some time, practically feasible implementations have long remained elusive. It should therefore not come as a surprise that the 2014 Nobel Prize in Chemistry was awarded to the scientists who, each in their own way, contributed to transforming super-resolution microscopy from a technological tour de force to a staple of the biologist’s toolkit. By overcoming the diffraction barrier, light microscopy could once again be established as an indispensable tool in an age where the importance of understanding life at the molecular level cannot be overstated. This review strives to provide the aspiring life science researcher with an introduction to optical microscopy, starting from the fundamental concepts governing compound and fluorescent confocal microscopy to the current state-of-the-art of super-resolution microscopy techniques and their applications.

  15. Consistency of Use and Effectiveness of Household Water Treatment among Indian Households Claiming to Treat Their Water.

    PubMed

    Rosa, Ghislaine; Clasen, Thomas

    2017-07-01

    Household water treatment (HWT) can improve drinking water quality and prevent disease if used correctly and consistently by populations at risk. Current international monitoring estimates by the Joint Monitoring Programme for water and sanitation suggest that at least 1.1 billion people practice HWT. These estimates, however, are based on surveys that may overstate the level of consistent use and do not address microbial effectiveness. We sought to assess how HWT is practiced among households identified as HWT users according to these monitoring standards. After a baseline survey (urban: 189 households, rural: 210 households) to identify HWT users, 83 urban and 90 rural households were followed up for 6 weeks. Consistency of reported HWT practices was high in both urban (100%) and rural (93.3%) settings, as was availability of treated water (based on self-report) in all three sampling points (urban: 98.8%, rural: 76.0%). Nevertheless, only 13.7% of urban and 25.8% of rural households identified at baseline as users of adequate HWT had water free of thermotolerant coliforms at all three water sampling points. Our findings raise questions about the value of the data gathered through the international monitoring of HWT as predictors of water quality in the home, as well as questioning the ability of HWT, as actually practiced by vulnerable populations, to reduce exposure to waterborne diseases.

  16. Workplace drug testing and worker drug use.

    PubMed

    Carpenter, Christopher S

    2007-04-01

    To examine the nature and extent of the association between workplace drug testing and worker drug use. Repeated cross-sections from the 2000 to 2001 National Household Surveys on Drug Abuse (NHSDA) and the 2002 National Survey on Drug Use and Health (NSDUH). Multivariate logistic regression models of the likelihood of marijuana use are estimated as a function of several different workplace drug policies, including drug testing. Specific questions about penalty severity and the likelihood of detection are used to further evaluate the nature of the association. Individuals whose employers perform drug tests are significantly less likely to report past month marijuana use, even after controlling for a wide array of worker and job characteristics. However, large negative associations are also found for variables indicating whether a firm has drug education, an employee assistance program, or a simple written policy about substance use. Accounting for these other workplace characteristics reduces-but does not eliminate-the testing differential. Frequent testing and severe penalties reduce the likelihood that workers use marijuana. Previous studies have interpreted the large negative correlation between workplace drug testing and employee substance use as representing a causal deterrent effect of drug testing. Our results using more comprehensive data suggest that these estimates have been slightly overstated due to omitted variables bias. The overall pattern of results remains largely consistent with the hypothesis that workplace drug testing deters worker drug use.

  17. (abstract) Scientific Objectivity and the Impact Hazard: Responsible Reporting Versus Crying Wolf

    NASA Technical Reports Server (NTRS)

    Weissman, Paul R.

    1993-01-01

    f comets and asteroids on the Earth pose a real hazard, comparable in probability to other hazards which society deems worthy of concern. As such, it is prudent and reasonable to investigate and institute means for evaluation of the exact nature of the hazard and possible means of mitigating the effects of impacts, primarily by preventing their occurrence through orbital deflection. Decisions as to the hazard and possible detection and deflection programs must be made through a rational public discussion of the issues, provided with the best possible information. Unfortunately, some individuals have tended to overstate the problem either in terms of the probability of impact or the expected effects of impacts. The net result of such actions is often to undermine public confidence in those attempting to promote an informal discussion of the impact hazard. This is particularily true in a time of declining budgets for both science and defense, and increased competition for federal R&D dollars. It is thus important that the community find means of promoting responsible actions by the members of the community, and for dealing with public release of information, within the bounds of academic and individual freedom. The purpose of this abstract is to promote a discussion of these issues within the community and to invite additional suggestions for methods to improve the providing of accurate information to the public, the media, and most importantly, to decision makers.

  18. Metabolomic analysis-Addressing NMR and LC-MS related problems in human feces sample preparation.

    PubMed

    Moosmang, Simon; Pitscheider, Maria; Sturm, Sonja; Seger, Christoph; Tilg, Herbert; Halabalaki, Maria; Stuppner, Hermann

    2017-10-31

    Metabolomics is a well-established field in fundamental clinical research with applications in different human body fluids. However, metabolomic investigations in feces are currently an emerging field. Fecal sample preparation is a demanding task due to high complexity and heterogeneity of the matrix. To gain access to the information enclosed in human feces it is necessary to extract the metabolites and make them accessible to analytical platforms like NMR or LC-MS. In this study different pre-analytical parameters and factors were investigated i.e. water content, different extraction solvents, influence of freeze-drying and homogenization, ratios of sample weight to extraction solvent, and their respective impact on metabolite profiles acquired by NMR and LC-MS. The results indicate that profiles are strongly biased by selection of extraction solvent or drying of samples, which causes different metabolites to be lost, under- or overstated. Additionally signal intensity and reproducibility of the measurement were found to be strongly dependent on sample pre-treatment steps: freeze-drying and homogenization lead to improved release of metabolites and thus increased signals, but at the same time induced variations and thus deteriorated reproducibility. We established the first protocol for extraction of human fecal samples and subsequent measurement with both complementary techniques NMR and LC-MS. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. A perspective on tritium versus carbon-14: ensuring optimal label selection in pharmaceutical research and development.

    PubMed

    Krauser, Joel A

    2013-01-01

    Tritium ((3) H) and carbon-14 ((14) C) labels applied in pharmaceutical research and development each offer their own distinctive advantages and disadvantages coupled with benefits and risks. The advantages of (3) H have a higher specific activity, shorter half-life that allows more manageable waste remediation, lower material costs, and often more direct synthetic routes. The advantages of (14) C offer certain analytical benefits and less potential for label loss. Although (3) H labels offer several advantages, they might be overlooked as a viable option because of the concerns about its drawbacks. A main drawback often challenged is metabolic liability. These drawbacks, in some cases, might be overstated leading to underutilization of a perfectly viable option. As a consequence, label selection may automatically default to (14) C, which is a more conservative approach. To challenge this '(14) C-by-default' approach, pharmaceutical agents with strategically selected (3) H-labeling positions based on non-labeled metabolism data have been successfully implemented and evaluated for (3) H loss. From in-house results, the long term success of projects clearly would benefit from a thorough, objective, and balanced assessment regarding label selection ((3) H or (14) C). This assessment should be based on available project information and scientific knowledge. Important considerations are project applicability (preclinical and clinical phases), synthetic feasibility, costs, and timelines. Copyright © 2013 John Wiley & Sons, Ltd.

  20. Prevalence and socio-demographic correlates of time spent cooking by adults in the 2005 UK Time Use Survey. Cross-sectional analysis.

    PubMed

    Adams, Jean; White, Martin

    2015-09-01

    This study aimed to document the prevalence and socio-demographic correlates of time spent cooking by adults in the 2005 UK Time-Use Survey. Respondents reported their main activities, in 10 minute slots, throughout one 24 hour period. Activities were coded into 30 pre-defined codes, including 'cooking, washing up'. Four measures of time spent cooking were calculated: any time spent cooking, 30 continuous minutes spent cooking, total time spent cooking, and longest continuous time spent cooking. Socio-demographic correlates were: age, employment, social class, education, and number of adults and children in the household. Analyses were stratified by gender. Data from 4214 participants were included. 85% of women and 60% of men spent any time cooking; 60% of women and 33% of men spent 30 continuous minutes cooking. Amongst women, older age, not being in employment, lower social class, greater education, and living with other adults or children were positively associated with time cooking. Few differences in time spent cooking were seen in men. Socio-economic differences in time spent cooking may have been overstated as a determinant of socio-economic differences in diet, overweight and obesity. Gender was a stronger determinant of time spent cooking than other socio-demographic variables. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  1. Gender Differences in the Interpretation of Experiences of Patients with Tuberculosis in Medellín, Colombia.

    PubMed

    Villa Vélez, Liliana; Arbeláez Montoya, María Patricia

    2015-01-01

    This study sought to determine gender differences in the interpretation of tuberculosis (TB) in a group of patients from the city of Medellín. This was a qualitative study, with the grounded theory method. Twelve semistructured interviews were applied to patients from both genders who were cured of TB. The sample was selected through convenience and for analysis the information was categorized through the Atlas Ti tool. Regarding the symptoms, the most reported is cough, but men manifest expectoration more frequently. Men overstated the symptoms, while women tend to minimize them. Women report mental impairment and emotional-type manifestations produced by the disease. Men and women expressed ignorance about the disease upon diagnosis. Both manifested fear of infection, work incapacity, loss of employment, rejection by others, and death. Also highlighted is the importance of family support and of the healthcare personnel. Women expressed shame in that others knew of their disease and mentioned greater intolerance with taking the medications. The gender role constructed culturally constitutes the central axis that explains how men and women interpret TB and can be modified by educational and accompaniment processes. Family support plays an important role in the healing process. Although common aspects exist, delving into the gender differences against the interpretation of TB may permit a different approach of the disease and better control of it.

  2. Tobacco taxes as a tobacco control strategy.

    PubMed

    Chaloupka, Frank J; Yurekli, Ayda; Fong, Geoffrey T

    2012-03-01

    Increases in tobacco taxes are widely regarded as a highly effective strategy for reducing tobacco use and its consequences. The voluminous literature on tobacco taxes is assessed, drawing heavily from seminal and recent publications reviewing the evidence on the impact of tobacco taxes on tobacco use and related outcomes, as well as that on tobacco tax administration. Well over 100 studies, including a growing number from low-income and middle-income countries, clearly demonstrate that tobacco excise taxes are a powerful tool for reducing tobacco use while at the same time providing a reliable source of government revenues. Significant increases in tobacco taxes that increase tobacco product prices encourage current tobacco users to stop using, prevent potential users from taking up tobacco use, and reduce consumption among those that continue to use, with the greatest impact on the young and the poor. Global experiences with tobacco taxation and tax administration have been used by WHO to develop a set of 'best practices' for maximising the effectiveness of tobacco taxation. Significant increases in tobacco taxes are a highly effective tobacco control strategy and lead to significant improvements in public health. The positive health impact is even greater when some of the revenues generated by tobacco tax increases are used to support tobacco control, health promotion and/or other health-related activities and programmes. In general, oppositional arguments that higher taxes will have harmful economic effects are false or overstated.

  3. Non-human primates in neuroscience research: The case against its scientific necessity.

    PubMed

    Bailey, Jarrod; Taylor, Kathy

    2016-03-01

    Public opposition to non-human primate (NHP) experiments is significant, yet those who defend them cite minimal harm to NHPs and substantial human benefit. Here we review these claims of benefit, specifically in neuroscience, and show that: a) there is a default assumption of their human relevance and benefit, rather than robust evidence; b) their human relevance and essential contribution and necessity are wholly overstated; c) the contribution and capacity of non-animal investigative methods are greatly understated; and d) confounding issues, such as species differences and the effects of stress and anaesthesia, are usually overlooked. This is the case in NHP research generally, but here we specifically focus on the development and interpretation of functional magnetic resonance imaging (fMRI), deep brain stimulation (DBS), the understanding of neural oscillations and memory, and investigation of the neural control of movement and of vision/binocular rivalry. The increasing power of human-specific methods, including advances in fMRI and invasive techniques such as electrocorticography and single-unit recordings, is discussed. These methods serve to render NHP approaches redundant. We conclude that the defence of NHP use is groundless, and that neuroscience would be more relevant and successful for humans, if it were conducted with a direct human focus. We have confidence in opposing NHP neuroscience, both on scientific as well as on ethical grounds. 2016 FRAME.

  4. Urgent revision required of NICE guidance relating to prevention of spread of vCJD through neurosurgical instruments.

    PubMed

    George, Kuriakose

    2014-04-01

    In 2006, NICE brought out guidance relating to prevention of vCJD through contaminated surgical instruments. This was with the aim of protecting patients born after 1997 who did not have any risk of developing vCJD through eating beef contaminated with BSE through the food chain. Many adult neurosurgical units did not pay much attention to this until 2013 when they were suddenly faced with these children who were now 16 and being admitted to the adult neurosurgical service rather than pediatric. The NICE guidance requires that most patients born after 1997 be operated on using a separate set of neurosurgical instruments than those born before this. This is proving to be a huge financial, as well as logistical, challenge and also a clinical risk as attention is being diverted to searching for the right kit when it should be spent on saving lives. It is now clear in 2013 that the risks that NICE feared were perhaps overstated as there is nowhere near the number of deaths from vCJD that NICE had feared would happen. Worldwide there have been only five cases whereby CJD was transmitted through contaminated neurosurgical instruments and the last case was in 1976. There have been no cases of vCJD transmission attributed to use of contaminated neurosurgical instruments. NICE should revisit this guidance urgently in view of these circumstances.

  5. Teaching health science students foundation motivational interviewing skills: use of motivational interviewing treatment integrity and self-reflection to approach transformative learning.

    PubMed

    M, Schoo A; S, Lawn; E, Rudnik; C, Litt J

    2015-12-21

    Many undergraduate and graduate-entry health science curricula have incorporated training in motivational interviewing (MI). However, to effectively teach skills that will remain with students after they graduate is challenging. The aims of this study were to find out self-assessed MI skills of health students and whether reflecting on the results can promote transformative learning. Thirty-six Australian occupational therapy and physiotherapy students were taught the principles of MI, asked to conduct a motivational interview, transcribe it, self-rate it using the Motivational Interviewing Treatment Integrity (MITI) tool and reflect on the experience. Student MI skills were measured using the reported MITI subscores. Student assignments and a focus group discussion were analysed to explore the student experience using the MITI tool and self-reflection to improve their understanding of MI principles. Students found MI challenging, although identified the MITI tool as useful for promoting self-reflection and to isolate MI skills. Students self-assessed their MI skills as competent and higher than scores expected from beginners. The results inform educational programs on how MI skills can be developed for health professional students and can result in transformative learning. Students may over-state their MI skills and strategies to reduce this, including peer review, are discussed. Structured self-reflection, using tools such as the MITI can promote awareness of MI skills and compliment didactic teaching methods.

  6. Pesticide Application among Farmers in the Catchment of Ashaiman Irrigation Scheme of Ghana: Health Implications

    PubMed Central

    Mattah, Memuna M.; Mattah, Precious A. D.; Futagbi, Godfred

    2015-01-01

    Pesticide use in modern day agriculture has increased tremendously. Pesticides are used to control pests and weeds, as well as protect crops from postharvest losses; however, their effects on humans and the environment cannot be overstated. This study examined pesticide acquisition, handling, and use among 120 farmers within the catchment of a small urban irrigation scheme. Also, in-depth interviews and focus group discussions were conducted among selected farmers through which further data was collected to augment that of the survey. Twelve types of pesticides, including herbicides, insecticides, and fungicides, were found in use in the study areas. Three main sources of information about pesticides were identified, 43.3% from extension officers, 39.2% from agrochemical dealers, and 10% from colleague farmers. Seventy-five percent (75%) of the respondents purchased the pesticides from agrochemical shops. Out of 74 farmers who were observed spraying pesticides on their farms, only 25.7% wore dresses that covered their whole body but without goggles. About sixty-seven percent (66.7%) of the farmers whose chemical got finished left the containers on their farms or threw them into the bushes around. The frequency of application was influenced by affordability and size of farm, among others. The study recommended that training of farmers on pesticide handling and use should be intensified. PMID:26798369

  7. Improved Estimates of the Benefits of Breastfeeding Using Sibling Comparisons to Reduce Selection Bias

    PubMed Central

    Evenhouse, Eirik; Reilly, Siobhan

    2005-01-01

    Objective Better measurement of the health and cognitive benefits of breastfeeding by using sibling comparisons to reduce sample selection bias. Data We use data on the breastfeeding history, physical and emotional health, academic performance, cognitive ability, and demographic characteristics of 16,903 adolescents from the first (1994) wave of the National Longitudinal Study of Adolescent Health. The sample includes 2,734 sibling pairs. Study Design We examine the relationship between breastfeeding history and 15 indicators of physical health, emotional health, and cognitive ability, using ordinary least squares and logit regression. For each indicator, we estimate, in addition to the usual between-family model, a within-family model to see whether differences in siblings' outcomes are associated with differences in the siblings' breastfeeding histories. Principal Findings Nearly all of the correlations found in the between-family model become statistically insignificant in the within-family model. The notable exception is a persistent positive correlation between breastfeeding and cognitive ability. These findings hold whether breastfeeding is measured in terms of duration or as a Yes/No variable. Conclusions This study provides persuasive evidence of a causal connection between breastfeeding and intelligence. However, it also suggests that nonexperimental studies of breastfeeding overstate some of its other long-term benefits, even if controls are included for race, ethnicity, income, and education. PMID:16336548

  8. Utilizing Radiofrequency Identification Technology to Improve Safety and Management of Blood Bank Supply Chains.

    PubMed

    Coustasse, Alberto; Meadows, Pamela; Hall, Robert S; Hibner, Travis; Deslich, Stacie

    2015-11-01

    The importance of efficiency in the supply chain of perishable products, such as the blood products used in transfusion services, cannot be overstated. Many problems can occur, such as the outdating of products, inventory management issues, patient misidentification, and mistransfusion. The purpose of this article was to identify the benefits and barriers associated with radiofrequency identification (RFID) usage in improving the blood bank supply chain. The methodology for this study was a qualitative literature review following a systematic approach. The review was limited to sources published from 2000 to 2014 in the English language. Sixty-five sources were found, and 56 were used in this research study. According to the finding of the present study, there are numerous benefits and barriers to RFID utilization in blood bank supply chains. RFID technology offers several benefits with regard to blood bank product management, including decreased transfusion errors, reduction of product loss, and more efficient inventory management. Barriers to RFID implementation include the cost associated with system implementation and patient privacy issues. Implementation of an RFID system can be a significant investment. However, when observing the positive impact that such systems may have on transfusion safety and inventory management, the cost associated with RFID systems can easily be justified. RFID in blood bank inventory management is vital to ensuring efficient product inventory management and positive patient outcomes.

  9. Endocrine manifestations and management of Prader-Willi syndrome.

    PubMed

    Emerick, Jill E; Vogt, Karen S

    2013-08-21

    Prader-Willi syndrome (PWS) is a complex genetic disorder, caused by lack of expression of genes on the paternally inherited chromosome 15q11.2-q13. In infancy it is characterized by hypotonia with poor suck resulting in failure to thrive. As the child ages, other manifestations such as developmental delay, cognitive disability, and behavior problems become evident. Hypothalamic dysfunction has been implicated in many manifestations of this syndrome including hyperphagia, temperature instability, high pain threshold, sleep disordered breathing, and multiple endocrine abnormalities. These include growth hormone deficiency, central adrenal insufficiency, hypogonadism, hypothyroidism, and complications of obesity such as type 2 diabetes mellitus. This review summarizes the recent literature investigating optimal screening and treatment of endocrine abnormalities associated with PWS, and provides an update on nutrition and food-related behavioral intervention. The standard of care regarding growth hormone therapy and surveillance for potential side effects, the potential for central adrenal insufficiency, evaluation for and treatment of hypogonadism in males and females, and the prevalence and screening recommendations for hypothyroidism and diabetes are covered in detail. PWS is a genetic syndrome in which early diagnosis and careful attention to detail regarding all the potential endocrine and behavioral manifestations can lead to a significant improvement in health and developmental outcomes. Thus, the important role of the provider caring for the child with PWS cannot be overstated.

  10. Is WISEP J060738.65+242953.4 Really a Magnetically Active, Pole-on L Dwarf?

    NASA Astrophysics Data System (ADS)

    Route, Matthew

    2017-07-01

    The interplay of rotation and manifested magnetic activity on ultracool dwarfs (UCDs) is of key importance for gathering clues regarding the operation of the dynamos within these objects. A number of magnetized UCDs host kG-strength magnetic fields. It was recently reported that the L8 dwarf WISEP J060738.65+242953.4 is a radio-emitting UCD that is likely observed pole-on, due to its lack of photometric variability and narrow spectral lines. Follow-up radio observations at Arecibo Observatory, together with a careful analysis of previously published details, however, suggest that the scientific and statistical significance of the radio and spectroscopic data has been overstated. If the UCD is observed along its aligned spin/magnetic axis, the absence of observed Hα activity may present challenges to the auroral model of UCD magnetism, although short-term or long-term cyclic magnetic activity may explain this behavior. The Monte Carlo simulations presented here suggest that the source probably rotates with v \\sin I=6{--}12 km s-1, indicating that its inclination angle and rotational velocity are unexceptional and that its angular momentum has evolved as expected for brown dwarfs observed in ˜1 Myr old clusters. The discovery and verification of the most rapidly and slowest rotating brown dwarfs places valuable constraints on the angular momentum evolution and magnetic activity histories of these objects.

  11. The Opposite of Denial: Social Learning at the Onset of the Ebola Emergency in Liberia.

    PubMed

    Abramowitz, Sharon; McKune, Sarah Lindley; Fallah, Mosoka; Monger, Josephine; Tehoungue, Kodjo; Omidian, Patricia A

    2017-01-01

    This study analyzes findings from a rapid-response community-based qualitative research initiative to study the content of Ebola-related communications and the transmission of Ebola-related behaviors and practices through mass media communications and social learning in Monrovia, Liberia during August-September 2014. Thirteen neighborhoods in the common Monrovia media market were studied to appraise the reach of health communications and outreach regarding Ebola prevention and response measures. A World Health Organization (WHO) research team collected data on social learning and Ebola knowledge, attitudes, and practices through focus group-based discussions and key informant interviews over a 14-day period to assess the spread of information during a period of rapidly escalating crisis. Findings show that during a 2-week period, Monrovia neighborhood residents demonstrated rapid changes in beliefs about the source of Ebola, modes of contagion, and infection prevention and control (IPC) practices, discarding incorrect information. Changes in practices tended to lag behind the acquisition of learning. Findings also show that many continued to support conspiracy theories even as correct information was acquired. The implications for community engagement are substantial: (1) Under conditions of accelerating mortality, communities rapidly assimilate health information and abandon incorrect information; (2) Behavior change is likely to lag behind changes in beliefs due to local physical, structural, sociocultural, and institutional constraints; (3) Reports of "resistance" in Monrovia during the Ebola response were overstated and based on a limited number of incidents, and failed to account for specific local conditions and constraints.

  12. A new mass mortality of juvenile Protoceratops and size-segregated aggregation behaviour in juvenile non-avian dinosaurs.

    PubMed

    Hone, David W E; Farke, Andrew A; Watabe, Mahito; Shigeru, Suzuki; Tsogtbaatar, Khishigjav

    2014-01-01

    Monodominant bonebeds are a relatively common occurrence for non-avian dinosaurs, and have been used to infer associative, and potentially genuinely social, behavior. Previously known assemblages are characterized as either mixed size-classes (juvenile and adult-sized specimens together) or single size-classes of individuals (only juveniles or only adult-sized individuals within the assemblage). In the latter case, it is generally unknown if these kinds of size-segregated aggregations characterize only a particular size stage or represent aggregations that happened at all size stages. Ceratopsians ("horned dinosaurs") are known from both types of assemblages. Here we describe a new specimen of the ceratopsian dinosaur Protoceratops andrewsi, Granger and Gregory 1923 from Mongolia representing an aggregation of four mid-sized juvenile animals. In conjunction with existing specimens of groups of P. andrewsi that includes size-clustered aggregations of young juveniles and adult-sized specimens, this new material provides evidence for some degree of size-clustered aggregation behaviour in Protoceratops throughout ontogeny. This continuity of size-segregated (and presumably age-clustered) aggregation is previously undocumented in non-avian dinosaurs. The juvenile group fills a key gap in the available information on aggregations in younger ceratopsians. Although we support the general hypothesis that many non-avian dinosaurs were gregarious and even social animals, we caution that evidence for sociality has been overstated and advocate a more conservative interpretation of some data of 'sociality' in dinosaurs.

  13. A New Mass Mortality of Juvenile Protoceratops and Size-Segregated Aggregation Behaviour in Juvenile Non-Avian Dinosaurs

    PubMed Central

    Hone, David W. E.; Farke, Andrew A.; Watabe, Mahito; Shigeru, Suzuki; Tsogtbaatar, Khishigjav

    2014-01-01

    Background Monodominant bonebeds are a relatively common occurrence for non-avian dinosaurs, and have been used to infer associative, and potentially genuinely social, behavior. Previously known assemblages are characterized as either mixed size-classes (juvenile and adult-sized specimens together) or single size-classes of individuals (only juveniles or only adult-sized individuals within the assemblage). In the latter case, it is generally unknown if these kinds of size-segregated aggregations characterize only a particular size stage or represent aggregations that happened at all size stages. Ceratopsians (“horned dinosaurs”) are known from both types of assemblages. Methods/Principal Findings Here we describe a new specimen of the ceratopsian dinosaur Protoceratops andrewsi, Granger and Gregory 1923 from Mongolia representing an aggregation of four mid-sized juvenile animals. In conjunction with existing specimens of groups of P. andrewsi that includes size-clustered aggregations of young juveniles and adult-sized specimens, this new material provides evidence for some degree of size-clustered aggregation behaviour in Protoceratops throughout ontogeny. This continuity of size-segregated (and presumably age-clustered) aggregation is previously undocumented in non-avian dinosaurs. Conclusions The juvenile group fills a key gap in the available information on aggregations in younger ceratopsians. Although we support the general hypothesis that many non-avian dinosaurs were gregarious and even social animals, we caution that evidence for sociality has been overstated and advocate a more conservative interpretation of some data of ‘sociality’ in dinosaurs. PMID:25426957

  14. Sorption characteristic of coal as regards of gas mixtures emitted in the process of the self-heating of coal

    NASA Astrophysics Data System (ADS)

    Wojtacha-Rychter, Karolina; Smoliński, Adam

    2017-10-01

    One of the most challenging tasks in the coal mining sector is the detection of endogenous fire risks. Under field conditions, the distance between the points where samples for the analyses are collected and the actual place where coal self-heating takes place may be quite remote. Coal is a natural sorbent with a diverse character of pore structures which are surrounded by fractures and cleavage planes constituting ideal spaces for the flow and adsorption of gases. The gases (methane, ethane, ethylene, propane, propylene, acetylene, carbon dioxide, carbon monoxide, hydrogen) released from the source of fire migrate through the seam and may be subject to adsorption, or they may cause the desorption of gases accumulated in coal. Therefore, the values of reference sample concentrations may be overstated or understated, respectively. The objective of this experimental study was to investigate the adsorption phenomena accompanying the flow of a multi-component gas mixture through a coal bed which may occur in situ. The research was conducted by means of a method based on a series of calorimetric/chromatographic measurements taken to determine the amount of gases released during coal heating at various temperatures under laboratory conditions. Based on the results obtained in the course of the experiments, it was concluded that the amount of gas adsorbed in the seam depends on the type of coal and the gas. Within the multi-component gas mixture, hydrocarbons demonstrated the largest sorption capacity, especially as concerns propylene.

  15. A modified approach for estimating the aquatic critical load of acid deposition in northern Saskatchewan, Canada

    NASA Astrophysics Data System (ADS)

    Whitfield, Colin J.; Mowat, Aidan C.; Scott, Kenneth A.; Watmough, Shaun A.

    2016-12-01

    Acid-sensitive ecosystems are found in northern Saskatchewan, which lies downwind of major sulphur (S) and nitrogen (N) emissions sources associated with the oil sands extraction industry. In order to protect these ecosystems against acidification, tolerance to acid deposition must be quantified. The suitability of the central empirical relationship used in the Steady-State Water Chemistry (SSWC) model to predict historical sulphate (SO4) concentrations was investigated, and an alternate approach for determining aquatic critical loads of acidity (CL(A)) was employed for the study lakes (n = 260). Critical loads of acidity were often low, with median values of 12-16 mmolc m-2 yr-1, with the lower value reflecting a region-specific limit for acid-neutralizing capacity identified in this study. Uncertain levels of atmospheric deposition in the region, however, are problematic for characterizing acidification risk. Accurate S and chloride (Cl) deposition are needed to identify catchment sources (and sinks) of these elements in the new approach for CL(A) calculation. Likewise, accurate depiction of atmospheric deposition levels can prove useful for evaluation of lake runoff estimates on which estimates of CL(A) are contingent. While CL(A) are low and exceedance may occur according to projected increases in S deposition in the near-term, S retention appears to be an important feature in many catchments and risk of acidification may be overstated should long-term S retention be occurring in peatlands.

  16. Antipsychotics and Amotivation

    PubMed Central

    Fervaha, Gagan; Takeuchi, Hiroyoshi; Lee, Jimmy; Foussias, George; Fletcher, Paul J; Agid, Ofer; Remington, Gary

    2015-01-01

    Antipsychotic drugs are thought to produce secondary negative symptoms, which can also exacerbate primary negative symptoms. In the present study, we examined whether motivational deficits in particular were related to antipsychotic treatment in patients with schizophrenia in a dose-dependent manner. Five hundred and twenty individuals with schizophrenia who were receiving antipsychotic monotherapy for at least 6 months and followed prospectively were included in the present study. Participants were receiving one of five antipsychotic medications (olanzapine, perphenazine, quetiapine, risperidone, or ziprasidone), and analyses were conducted for patients receiving each drug separately. Analysis of covariance models were constructed to examine the effect of antipsychotic dose on level of motivational impairment, controlling for selected demographic and clinical variables (eg, positive symptoms). Level of motivation, or deficits therein, were evaluated using a derived measure from the Quality of Life Scale, and in addition with scores derived from the Positive and Negative Syndrome Scale. Antipsychotic dose was not related to the level of amotivation for any of the medications examined. Moreover, severity of sedation was not significantly related to the degree of amotivation. One hundred and twenty-one individuals were identified as antipsychotic-free at baseline, and after 6 months of antipsychotic treatment, no change in motivation was found. Chronic treatment with antipsychotics does not necessarily impede or enhance goal-directed motivation in patients with schizophrenia. It is possible that the negative impact of antipsychotics in this regard is overstated; conversely, the present results also indicate that we must look beyond antipsychotics in our efforts to improve motivation. PMID:25567425

  17. Antipsychotics and amotivation.

    PubMed

    Fervaha, Gagan; Takeuchi, Hiroyoshi; Lee, Jimmy; Foussias, George; Fletcher, Paul J; Agid, Ofer; Remington, Gary

    2015-05-01

    Antipsychotic drugs are thought to produce secondary negative symptoms, which can also exacerbate primary negative symptoms. In the present study, we examined whether motivational deficits in particular were related to antipsychotic treatment in patients with schizophrenia in a dose-dependent manner. Five hundred and twenty individuals with schizophrenia who were receiving antipsychotic monotherapy for at least 6 months and followed prospectively were included in the present study. Participants were receiving one of five antipsychotic medications (olanzapine, perphenazine, quetiapine, risperidone, or ziprasidone), and analyses were conducted for patients receiving each drug separately. Analysis of covariance models were constructed to examine the effect of antipsychotic dose on level of motivational impairment, controlling for selected demographic and clinical variables (eg, positive symptoms). Level of motivation, or deficits therein, were evaluated using a derived measure from the Quality of Life Scale, and in addition with scores derived from the Positive and Negative Syndrome Scale. Antipsychotic dose was not related to the level of amotivation for any of the medications examined. Moreover, severity of sedation was not significantly related to the degree of amotivation. One hundred and twenty-one individuals were identified as antipsychotic-free at baseline, and after 6 months of antipsychotic treatment, no change in motivation was found. Chronic treatment with antipsychotics does not necessarily impede or enhance goal-directed motivation in patients with schizophrenia. It is possible that the negative impact of antipsychotics in this regard is overstated; conversely, the present results also indicate that we must look beyond antipsychotics in our efforts to improve motivation.

  18. Ensuring PhD development of responsible conduct of research behaviors: who's responsible?

    PubMed

    Titus, Sandra L; Ballou, Janice M

    2014-03-01

    The importance of public confidence in scientific findings and trust in scientists cannot be overstated. Thus, it becomes critical for the scientific community to focus on enhancing the strategies used to educate future scientists on ethical research behaviors. What we are lacking is knowledge on how faculty members shape and develop ethical research standards with their students. We are presenting the results of a survey with 3,500 research faculty members. We believe this is the first report on how faculty work with and educate their PhD students on basic research standards. Specifically, we wanted to determine whether individual faculty members, who are advisors or mentors, differ in how they implemented components of responsible conduct of research (RCR) with their PhD students. Mentors were more likely than advisors or supervisors to report working with all of their PhDs, who graduated in the last 5 years, on the 17 recognized critical components of RCR training and research skill development. We also found about half of the faculty members believe RCR is an institutional responsibility versus a faculty responsibility. Less than a quarter have had opportunities to participate in faculty training to be a better mentor, advisor, or research teacher, and about one third of faculty did not or could not remember whether they had guidelines related to their responsibilities to PhD students. We discuss the implications of our findings and focus on ways that PhD research mentoring can be enhanced.

  19. Updates on chemical and biological research on botanical ingredients in dietary supplements.

    PubMed

    Pawar, Rahul S; Tamta, Hemlata; Ma, Jun; Krynitsky, Alexander J; Grundel, Erich; Wamer, Wayne G; Rader, Jeanne I

    2013-05-01

    Increased use of dietary supplements is a phenomenon observed worldwide. In the USA, more than 40% of the population recently reported using complementary and alternative medicines, including botanical dietary supplements. Perceptions that such dietary supplements are natural and safe, may prevent disease, may replace prescription medicines, or may make up for a poor diet, play important roles in their increased use. Toxicity of botanical dietary supplements may result from the presence of naturally occurring toxic constituents or from contamination or adulteration with pharmaceutical agents, heavy metals, mycotoxins, pesticides, or bacteria, misidentification of a plant species in a product, formation of electrophilic metabolites, organ-specific reactions, or botanical-drug interactions. The topics discussed in this review illustrate several issues in recent research on botanical ingredients in dietary supplements. These include (1) whether 1,3-dimethylamylamine is a natural constituent of rose geranium (Pelargonium graveolens), (2) how analysis of the components of dietary supplements containing bitter melon (Momordica charantia) is essential to understanding their potential biological effects, and (3) how evolving methods for in vitro studies on botanical ingredients can contribute to safety evaluations. The virtual explosion in the use of botanical ingredients in hundreds of products presents a considerable challenge to the analytical community, and the need for appropriate methods cannot be overstated. We review recent developments and use of newer and increasingly sensitive methods that can contribute to increasing the safety and quality of botanical ingredients in dietary supplements.

  20. Regionalisation of Hydrological Indices to Assess Land-Use Change Impacts in the Tropical Andes

    NASA Astrophysics Data System (ADS)

    Buytaert, W.; Ochoa Tocachi, B. F.

    2014-12-01

    Andean ecosystems are major water sources for cities and communities located in the Tropical Andes; however, there is a considerable lack of knowledge about their hydrology. Two problems are especially important: (i) the lack of monitoring to assess the impacts of historical land-use and cover change and degradation (LUCCD) at catchment scale, and (ii) the high variability in climatic and hydrological conditions that complicate the evaluation of land management practices. This study analyses how a reliable LUCCD impacts assessment can be performed in an environment of high variability combined with data-scarcity and low-quality records. We use data from participatory hydrological monitoring activities in 20 catchments distributed along the tropical Andes. A set of 46 hydrological indices is calculated and regionalized by relating them to 42 physical catchment properties. Principal Component Analysis (PCA) is performed to maximise available data while minimising redundancy in the sets of variables. Hydrological model parameters are constrained by estimated indices, and different behavioural predictions are assembled to provide a generalised response on which we assess LUCCD impacts. Results from this methodology show that the attributed effects of LUCCD in pair-wise catchment comparisons may be overstated or hidden by different sources of uncertainty, including measurement inaccuracies and model structural errors. We propose extrapolation and evaluation in ungauged catchments as a way to regionalize LUCCD predictions and to provide statistically significant conclusions in the Andean region. These estimations may deliver reliable knowledge to evaluate the hydrological impact of different watershed management practices.

  1. A cluster design controlled trial of arts-based observational skills training in primary care.

    PubMed

    Kirklin, Deborah; Duncan, Jane; McBride, Sandy; Hunt, Sam; Griffin, Mark

    2007-04-01

    To investigate whether the observational skills of doctors and nurses can be improved by arts-based observational skills training. We carried out a cluster design, controlled trial involving 42 general practitioners and 26 primary care nurses in 12 primary care practices in London. Six practices were allocated to the intervention arm and 6 to the control arm. The intervention group received 90 minutes of arts-based observational skills training. The control group received practical training in the management of psoriasis. Before and after this, control and intervention participants were asked to describe 3 dermatological photographs. Descriptions were scored blindly against a predetermined marking key. Participants completed a questionnaire about the intervention, and about their own confidence in diagnosing and referring suspicious pigmented skin lesions. Post-intervention scores were significantly higher in the intervention group compared with the control group (P < 0.001). The majority of participants judged the intervention relevant, enjoyable and valuable. A majority lacked confidence in their dermatological knowledge and skills. This study provides statistically significant evidence that arts-based observational skills training can improve the observational skills of doctors and nurses. It is important not to overstate the clinical significance of these findings, and to recognise that observational skills are just one of many complex and subtle factors affecting the quality of the clinical process. Further research is needed to assess the existence, nature and clinical significance of longer-term benefits, and to identify differences between professional groups.

  2. The use of 'arms-length' organizations for health system change in Ontario, Canada: some observations by insiders.

    PubMed

    Pink, George H; Leatt, Peggy

    2003-01-01

    During the past decade, there has been substantial health system reform in the United States, United Kingdom, New Zealand, and many other countries. For the most part, Canada has not pursued 'big bang' health system change but rather a variety of strategies to achieve incremental change. In this paper, we present the ways in which three arms-length organizations have been used by government to effect incremental system change in Ontario during the past several years. We observe that, (1) the influence of politics and political interference can be reduced through an arms-length organization; (2) an arms-length organization with the power to make decisions entails more political risk for government and encounters more scrutiny and criticism by providers and the media than an organization with the power to recommend only; (3) an arms-length organization with a limited lifespan faces more delaying tactics by adversely affected parties than an organization without a limited lifespan; (4) an arms-length organization with perceived influence may attract causes that are not related to its mandate; (5) the importance and difficulty of communicating complex information about system change to a wide variety of audiences cannot be overstated; (6) system change informed by the use of expert opinion encounters less provider resistance and may result in better decisions; and (7) the reputation of the Chair and the perceived competence and experience of the CEO are critical success factors in the success of an arms-length organization.

  3. Using PVDF for wavenumber-frequency analysis and excitation of guided waves

    NASA Astrophysics Data System (ADS)

    Ren, Baiyang; Cho, Hwanjeong; Lissenden, Cliff J.

    2018-04-01

    The role of transducers in nondestructive evaluation using ultrasonic guided waves cannot be overstated. Energy conversion from electrical to mechanical for actuation and then back to electrical for signal processing broadly describes transduction, but there are many other aspects of transducers that determine their effectiveness. Recently we have reported on polyvinylidene difluoride (PVDF) array sensors that enable determination of the wavenumber spectrum, which enables modal content in the received signal to be characterized. Modal content is an important damage indicator because, for example, mode conversion is a frequent consequence of wave interaction with defects. Some of the positive attributes of PVDF sensors are: broad frequency bandwidth, compliance for use on curved surfaces, limited influence on the passing wave, minimal cross-talk between elements, low profile, low mass, and inexpensive. The anisotropy of PVDF films also enables them to receive either Lamb waves or shear horizontal waves by proper alignment of the material principal coordinate axes. Placing a patterned set of electrodes on the PVDF film provides data from an array of elements. A linear array of elements is used to enable a 2D fast Fourier transform to determine the wavenumber spectrum of both Lamb waves and shear horizontal waves in an aluminum plate. Moreover, since PVDF film can sustain high voltage excitation, high power pulsers can be used to improve the signal-to-noise ratio. The capability of PVDF as a transmitter has been demonstrated with high voltage excitation.

  4. Consistency of Use and Effectiveness of Household Water Treatment Practices Among Urban and Rural Populations Claiming to Treat Their Drinking Water at Home: A Case Study in Zambia.

    PubMed

    Rosa, Ghislaine; Kelly, Paul; Clasen, Thomas

    2016-02-01

    Household water treatment (HWT) can improve drinking water quality and prevent disease, if used correctly and consistently. While international monitoring suggests that 1.8 billion people practice HWT, these estimates are based on household surveys that may overstate the level of consistent use and do not address microbiological effectiveness. We sought to examine how HWT is practiced among households identified as HWT users according to international monitoring standards. Case studies were conducted in urban and rural Zambia. After a baseline survey (urban: 203 households, rural: 276 households) to identify HWT users, 95 urban and 82 rural households were followed up for 6 weeks. Consistency of HWT reporting was low; only 72.6% of urban and 50.0% of rural households reported to be HWT users in the subsequent visit. Similarly, availability of treated water was low, only 23.3% and 4.2% of urban and rural households, respectively, had treated water on all visits. Drinking water was significantly worse than source water in both settings. Only 19.6% of urban and 2.4% of rural households had drinking water free of thermotolerant coliforms on all visits. Our findings raise questions about the value of the data gathered through the international monitoring of HWT practices as predictors of water quality in the home. © The American Society of Tropical Medicine and Hygiene.

  5. Workplace Drug Testing and Worker Drug Use

    PubMed Central

    Carpenter, Christopher S

    2007-01-01

    Objective To examine the nature and extent of the association between workplace drug testing and worker drug use. Data Sources Repeated cross-sections from the 2000 to 2001 National Household Surveys on Drug Abuse (NHSDA) and the 2002 National Survey on Drug Use and Health (NSDUH). Study Design Multivariate logistic regression models of the likelihood of marijuana use are estimated as a function of several different workplace drug policies, including drug testing. Specific questions about penalty severity and the likelihood of detection are used to further evaluate the nature of the association. Principal Findings Individuals whose employers perform drug tests are significantly less likely to report past month marijuana use, even after controlling for a wide array of worker and job characteristics. However, large negative associations are also found for variables indicating whether a firm has drug education, an employee assistance program, or a simple written policy about substance use. Accounting for these other workplace characteristics reduces—but does not eliminate—the testing differential. Frequent testing and severe penalties reduce the likelihood that workers use marijuana. Conclusions Previous studies have interpreted the large negative correlation between workplace drug testing and employee substance use as representing a causal deterrent effect of drug testing. Our results using more comprehensive data suggest that these estimates have been slightly overstated due to omitted variables bias. The overall pattern of results remains largely consistent with the hypothesis that workplace drug testing deters worker drug use. PMID:17362218

  6. Estimates of over-diagnosis of breast cancer due to population-based mammography screening in South Australia after adjustment for lead time effects.

    PubMed

    Beckmann, Kerri; Duffy, Stephen W; Lynch, John; Hiller, Janet; Farshid, Gelareh; Roder, David

    2015-09-01

    To estimate over-diagnosis due to population-based mammography screening using a lead time adjustment approach, with lead time measures based on symptomatic cancers only. Women aged 40-84 in 1989-2009 in South Australia eligible for mammography screening. Numbers of observed and expected breast cancer cases were compared, after adjustment for lead time. Lead time effects were modelled using age-specific estimates of lead time (derived from interval cancer rates and predicted background incidence, using maximum likelihood methods) and screening sensitivity, projected background breast cancer incidence rates (in the absence of screening), and proportions screened, by age and calendar year. Lead time estimates were 12, 26, 43 and 53 months, for women aged 40-49, 50-59, 60-69 and 70-79 respectively. Background incidence rates were estimated to have increased by 0.9% and 1.2% per year for invasive and all breast cancer. Over-diagnosis among women aged 40-84 was estimated at 7.9% (0.1-12.0%) for invasive cases and 12.0% (5.7-15.4%) when including ductal carcinoma in-situ (DCIS). We estimated 8% over-diagnosis for invasive breast cancer and 12% inclusive of DCIS cancers due to mammography screening among women aged 40-84. These estimates may overstate the extent of over-diagnosis if the increasing prevalence of breast cancer risk factors has led to higher background incidence than projected. © The Author(s) 2015.

  7. Comparison of SMR, PMR, and PCMR in a cohort of union members potentially exposed to diesel exhaust emissions.

    PubMed Central

    Wong, O; Morgan, R W; Kheifets, L; Larson, S R

    1985-01-01

    A comparison of cause specific standarised mortality ratios (SMRs) and proportionate mortality ratios (PMRs) or proportionate cancer mortality ratios (PCMRs) was made based on the mortality experience of a cohort of 34 156 members of a heavy equipment operators union. Two types of PMRs or PCMRs were used in the comparison: those based on all deaths and those based on deaths known to the union only. The comparison indicated that, for the entire cohort, both types of PMRs were poor indicators for cancer risk and produced a large number of false positives. On the other hand, PCMRs appeared to be better than PMRs for assessing the direction of site specific cancer risk, but they tended to overstate the magnitude of risk. Analysis by duration of union membership or latency indicated that PMRs or PCMRs based on deaths known to the union tended to overestimate the risk of lung cancer by disproportionately larger amounts in groups with shorter time than in groups with longer time. This differential bias had the net effect of reducing the gradient of any trend or eliminating the trend entirely. In conclusion, PMR or PCMR, based on reasonably sufficient death ascertainment, has a certain usefulness in generating hypotheses, but they are not useful or reliable in measuring the magnitude of risk or in detecting trends in dose response analysis. No conclusion should be drawn from either PMR or PCMR. PMID:2410011

  8. The education, training, and specialization of surgeons: turn-of-the-century America and its postgraduate medical schools.

    PubMed

    Rutkow, Ira

    2013-12-01

    To understand the institutions, personnel, and events that shaped postgraduate medical schools in late 19th- and early 20th-century America. In a little remembered chapter of American surgical medical history, postgraduate medical schools played a decisive role in surgery's march toward professionalization and specialization. While William Halsted was first establishing his training program in Baltimore, medical facilities such as the New York Polyclinic and the New York Post-Graduate were already turning out thousands of physicians who considered themselves "specialists" in surgery. An analysis of the published and unpublished medical and lay literature relating to the nation's postgraduate medical schools. The founding of postgraduate medical schools in turn-of-the-century America was a key event in the acceptance of surgery as a legitimate specialty within the whole of medicine. These little remembered institutions laid the foundation for the blossoming of surgical care and the extraordinary clinical advances that followed. Postgraduate medical schools, particularly the New York Polyclinic and the New York Post-Graduate, were dominant influences in shaping the early history of surgery in America. These institutions brought the pressure for specialization in surgery to the forefront of discussions about medical education and training. For the first time, a large number of practitioners were offered a formalized surgical experience in a busy urban medical facility. As a result, and despite their being long forgotten, the importance of postgraduate medical schools in our nation's surgical history cannot be overstated.

  9. Trends in Preventable Inpatient and Emergency Department Utilization in California Between 2012 and 2015: The Role of Health Insurance Coverage and Primary Care Supply.

    PubMed

    Cunningham, Peter; Sheng, Yaou

    2018-06-01

    Expansions of health insurance coverage tend to increase hospital emergency department (ED) utilization and inpatient admissions. However, provisions in the Affordable Care Act that expanded primary care supply were intended in part to offset the potential for increased hospital utilization. To examine the association between health insurance coverage, primary care supply, and ED and inpatient utilization, and to assess how both factors contributed to trends in utilization in California between 2012 and 2015. Population-based measures of ED and inpatient utilization, insurance coverage, and primary care supply were constructed for California counties for the years 2012 through 2015. Fixed effects regression analysis is used to examine the association between health insurance coverage, primary care supply, and rates of preventable ED and inpatient utilization. Higher levels of Medicaid coverage in a county are associated with higher levels of preventable ED and inpatient utilization, although greater numbers of primary care practitioners and Federally Qualified Health Centers reduce this type of utilization. Increases in coverage accelerated a long-term increase in ED visits and prevented an even larger decrease in inpatient admissions, but changes in coverage do not fully explain these underlying trends. Increases in primary care supply offset the effects of coverage changes only modestly. Policymakers should not overstate the impact of the Affordable Care Act on increasing ED visits, and should focus on better understanding the underlying factors that are driving the trends.

  10. Estimating the effects of light rail transit on health care costs.

    PubMed

    Stokes, Robert J; MacDonald, John; Ridgeway, Greg

    2008-03-01

    In recent years, there has been a proliferation of research on the effects of the built environment, including mass transit systems, on health-related outcomes. While there is general agreement that the built environment affects travel choices and physical activity, it remains unclear how much of a public health benefit (in dollars) can be derived from land use policies that support walking, biking, and transit. In the present study, we develop a model to assess the potential cost savings in public health that will be realized from the investment in a new light rail transit system in Charlotte, NC. Relying on estimates of future riders, area obesity rates, and the effects of public transit on physical activity (daily walking to and from the transit stations), we simulated the potential yearly public health cost savings associated with this infrastructure investment. Our results indicate that investing in light rail is associated with a 9-year cumulative public health cost savings of dollars 12.6 million. While these results suggest that there is a sizable public health benefit associated with the adoption of light rail, they also indicate that the effects are relatively small compared to the costs associated with constructing and operating such systems. These findings suggest that planning efforts that focus solely on the health impact of modifications in the built environment are likely to overstate the economic benefits. Public health benefits should be considered along with broader environmental health benefits.

  11. Public debates driven by incomplete scientific data: The cases of evolution theory, global warming and H1N1 pandemic influenza

    NASA Astrophysics Data System (ADS)

    Galam, Serge

    2010-09-01

    Public debates driven by incomplete scientific data where nobody can claim absolute certainty, due to the current state of scientific knowledge, are studied. The cases of evolution theory, global warming and H1N1 pandemic influenza are investigated. The first two are of controversial impact while the third is more neutral and resolved. To adopt a cautious balanced attitude based on clear but inconclusive data appears to be a lose-out strategy. In contrast overstating arguments with incorrect claims which cannot be scientifically refuted appears to be necessary but not sufficient to eventually win a public debate. The underlying key mechanisms of these puzzling and unfortunate conclusions are identified using the Galam sequential probabilistic model of opinion dynamics (Galam, 2002 [4], Galam, 2005 [18], Galam and Jacobs, 2007 [19]). It reveals that the existence of inflexible agents and their respective proportions are the instrumental parameters to determine the faith of incomplete scientific data in public debates. Acting on one’s own inflexible proportion modifies the topology of the flow diagram, which in turn can make irrelevant initial supports. On the contrary focusing on open-minded agents may be useless given some topologies. When the evidence is not as strong as claimed, the inflexibles rather than the data are found to drive the opinion of the population. The results shed a new but disturbing light on designing adequate strategies to win a public debate.

  12. Pain Management for Gynecologic Procedures in the Office.

    PubMed

    Ireland, Luu Doan; Allen, Rebecca H

    2016-02-01

    Satisfactory pain control for women undergoing office gynecologic procedures is critical for both patient comfort and procedure success. Therefore, it is important for clinicians to be aware of the safety and efficacy of different pain control regimens. This article aimed to review the literature regarding pain control regimens for procedures such as endometrial biopsy, intrauterine device insertion, colposcopy and loop electrosurgical excisional procedure, uterine aspiration, and hysteroscopy. A search of published literature using PubMed was conducted using the following keywords: "pain" or "anesthesia." These terms were paired with the following keywords: "intrauterine device" or "IUD," "endometrial biopsy," "uterine aspiration" or "abortion," "colposcopy" or "loop electrosurgical excisional procedure" or "LEEP," "hysteroscopy" or "hysteroscopic sterilization." The search was conducted through July 2015. Articles were hand reviewed and selected by the authors for study quality. Meta-analyses and randomized controlled trials were prioritized. Although local anesthesia is commonly used for gynecologic procedures, a multimodal approach may be more effective including oral medication, a dedicated emotional support person, and visual or auditory distraction. Women who are nulliparous, are postmenopausal, have a history of dysmenorrhea, or suffer from anxiety are more likely to experience greater pain with gynecologic procedures. Evidence for some interventions exists; however, the interpretation of intervention comparisons is limited by the use of different regimens, pain measurement scales, patient populations, and procedure techniques. There are many options for pain management for office gynecologic procedures, and depending on the procedure, different modalities may work best. The importance of patient counseling and selection cannot be overstated.

  13. Potential effects of gas hydrate on human welfare

    USGS Publications Warehouse

    Kvenvolden, K.A.

    1999-01-01

    For almost 30 years, serious interest has been directed toward natural gas hydrate, a crystalline solid composed of water and methane, as a potential (i) energy resource, (ii) factor in global climate change, and (iii) sub-marine geohazard. Although each of these issues can affect human welfare, only (iii) is considered to be of immediate importance. Assessments of gas hydrate as an energy resource have often been overly optimistic, based in part on its very high methane content and on its worldwide occurrence in continental margins. Although these attributes are attractive, geologic settings, reservoir properties, and phase-equilibria considerations diminish the energy resource potential of natural gas hydrate. The possible role of gas hydrate in global climate change has been often overstated. Although methane is a 'greenhouse' gas in the atmosphere, much methane from dissociated gas hydrate may never reach the atmosphere, but rather may be converted to carbon dioxide and sequestered by the hydrosphere/biosphere before reaching the atmosphere. Thus, methane from gas hydrate may have little opportunity to affect global climate change. However, submarine geohazards (such as sediment instabilities and slope failures on local and regional scales, leading to debris flows, slumps, slides, and possible tsunamis) caused by gas-hydrate dissociation are of immediate and increasing importance as humankind moves to exploit seabed resources in ever-deepening waters of coastal oceans. The vulnerability of gas hydrate to temperature and sea level changes enhances the instability of deep-water oceanic sediments, and thus human activities and installations in this setting can be affected.

  14. Bayesian probabilistic population projections for all countries

    PubMed Central

    Raftery, Adrian E.; Li, Nan; Ševčíková, Hana; Gerland, Patrick; Heilig, Gerhard K.

    2012-01-01

    Projections of countries’ future populations, broken down by age and sex, are widely used for planning and research. They are mostly done deterministically, but there is a widespread need for probabilistic projections. We propose a Bayesian method for probabilistic population projections for all countries. The total fertility rate and female and male life expectancies at birth are projected probabilistically using Bayesian hierarchical models estimated via Markov chain Monte Carlo using United Nations population data for all countries. These are then converted to age-specific rates and combined with a cohort component projection model. This yields probabilistic projections of any population quantity of interest. The method is illustrated for five countries of different demographic stages, continents and sizes. The method is validated by an out of sample experiment in which data from 1950–1990 are used for estimation, and applied to predict 1990–2010. The method appears reasonably accurate and well calibrated for this period. The results suggest that the current United Nations high and low variants greatly underestimate uncertainty about the number of oldest old from about 2050 and that they underestimate uncertainty for high fertility countries and overstate uncertainty for countries that have completed the demographic transition and whose fertility has started to recover towards replacement level, mostly in Europe. The results also indicate that the potential support ratio (persons aged 20–64 per person aged 65+) will almost certainly decline dramatically in most countries over the coming decades. PMID:22908249

  15. Helpful and Hindering Factors in Psychodrama Field Training: A Longitudinal Mixed Methods Study of Student Development.

    PubMed

    Azoulay, Bracha; Orkibi, Hod

    2018-01-01

    Although the literature indicates that students in mental health professions start to form their professional identity and competence in graduate school, there are few studies on the in-training experience of creative arts therapies students. This mixed methods study examined how five first-year students in a psychodrama master's degree program in Israel experienced their field training, with the aim of identifying the factors likely to promote or hinder the development of their professional identity and sense of professional ability. Longitudinal data were collected weekly throughout the 20-week field training experience. The students reported qualitatively on helpful and hindering factors and were assessed quantitatively on questionnaires measuring professional identity, perceived demands-abilities fit, client involvement, and therapy session evaluations. A thematic analysis of the students' reports indicated that a clear and defined setting and structure, observing the instructor as a role model, actively leading parts of the session, and observing fellow students were all helpful factors. The hindering factors included role confusion, issues related to coping with client resistance and disciplinary problems, as well as school end-of-year activities that disrupted the continuity of therapy. The quantitative results indicated that students' professional identity did not significantly change over the year, whereas a U-shaped curve trajectory characterized the changes in demands-abilities fit and other measures. Students began their field training with an overstated sense of ability that soon declined and later increased. These findings provide indications of which helping and hindering factors should be maximized and minimized, to enhance students' field training.

  16. Helpful and Hindering Factors in Psychodrama Field Training: A Longitudinal Mixed Methods Study of Student Development

    PubMed Central

    Azoulay, Bracha; Orkibi, Hod

    2018-01-01

    Although the literature indicates that students in mental health professions start to form their professional identity and competence in graduate school, there are few studies on the in-training experience of creative arts therapies students. This mixed methods study examined how five first-year students in a psychodrama master’s degree program in Israel experienced their field training, with the aim of identifying the factors likely to promote or hinder the development of their professional identity and sense of professional ability. Longitudinal data were collected weekly throughout the 20-week field training experience. The students reported qualitatively on helpful and hindering factors and were assessed quantitatively on questionnaires measuring professional identity, perceived demands-abilities fit, client involvement, and therapy session evaluations. A thematic analysis of the students’ reports indicated that a clear and defined setting and structure, observing the instructor as a role model, actively leading parts of the session, and observing fellow students were all helpful factors. The hindering factors included role confusion, issues related to coping with client resistance and disciplinary problems, as well as school end-of-year activities that disrupted the continuity of therapy. The quantitative results indicated that students’ professional identity did not significantly change over the year, whereas a U-shaped curve trajectory characterized the changes in demands-abilities fit and other measures. Students began their field training with an overstated sense of ability that soon declined and later increased. These findings provide indications of which helping and hindering factors should be maximized and minimized, to enhance students’ field training. PMID:29515504

  17. The Problem of Rarity: Estimation of Prevalence in Rare Disease.

    PubMed

    Auvin, Stéphane; Irwin, John; Abi-Aad, Paul; Battersby, Alysia

    2018-05-01

    From a disease's first description to its wider recognition, factors such as changes over time in diagnostic criteria, available therapies, and subsequent mortality rates may influence diagnosed prevalence of rare diseases. To propose a novel methodology for estimating the true prevalence of rare diseases using current incidence adjusted to changing diagnostic practice over time. This article focuses on rare diseases whose diagnosis may have changed over time, and raises the hypothesis that prevalence calculated from current incidence may be higher than diagnosed prevalence, which may lag behind the current disease definition and diagnostic methods. A rare epileptic encephalopathy, Dravet syndrome (DS), is explored as an illustrative example. A targeted literature review was performed for DS to identify all reported incidence, prevalence, and mortality and depict how diagnostic practice has evolved over time. A conceptual model was developed to calculate prevalence derived from current incidence figures alone (incidence-derived prevalence) or incidence adjusted with factors that cause a diagnostic drag (diagnostic awareness-adjusted prevalence). We identified sufficient publications of incidence and prevalence to test the conceptual model. For pediatric patients with DS, diagnosed prevalence in the field (as reported in current literature) matches incidence-derived prevalence, whereas for adult patients, it is overestimated by incidence-derived prevalence, but not by diagnostic awareness-adjusted prevalence. Care should be taken with current incidence-derived prevalence figures to not overstate the prevalence in rare diseases, as methodological challenges in counting small populations, coupled with advances in rare disease discovery, may cause discrepancies. Copyright © 2018 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

  18. Using Caffeine Pills for Performance Enhancement. An Experimental Study on University Students' Willingness and Their Intention to Try Neuroenhancements.

    PubMed

    Brand, Ralf; Koch, Helen

    2016-01-01

    Recent research has indicated that university students sometimes use caffeine pills for neuroenhancement (NE; non-medical use of psychoactive substances or technology to produce a subjective enhancement in psychological functioning and experience), especially during exam preparation. In our factorial survey experiment, we manipulated the evidence participants were given about the prevalence of NE amongst peers and measured the resulting effects on the psychological predictors included in the Prototype-Willingness Model of risk behavior. Two hundred and thirty-one university students were randomized to a high prevalence condition (read faked research results overstating usage of caffeine pills amongst peers by a factor of 5; 50%), low prevalence condition (half the estimated prevalence; 5%) or control condition (no information about peer prevalence). Structural equation modeling confirmed that our participants' willingness and intention to use caffeine pills in the next exam period could be explained by their past use of neuroenhancers, attitude to NE and subjective norm about use of caffeine pills whilst image of the typical user was a much less important factor. Provision of inaccurate information about prevalence reduced the predictive power of attitude with respect to willingness by 40-45%. This may be because receiving information about peer prevalence which does not fit with their perception of the social norm causes people to question their attitude. Prevalence information might exert a deterrent effect on NE via the attitude-willingness association. We argue that research into NE and deterrence of associated risk behaviors should be informed by psychological theory.

  19. Ayahuasca's entwined efficacy: An ethnographic study of ritual healing from 'addiction'.

    PubMed

    Talin, Piera; Sanabria, Emilia

    2017-06-01

    A range of studies has demonstrated the efficacy of the psychoactive Amazonian brew ayahuasca in addressing substance addiction. These have revealed that physiological and psychological mechanisms are deeply enmeshed. This article focuses on how interactive ritual contexts support the healing effort. The study of psychedelic-assisted treatments for addiction has much to gain from ethnographic analyses of healing experiences within the particular ecologies of use and care, where these interventions are rendered efficacious. This is an ethnographically grounded, qualitative analysis of addiction-recovery experiences within ayahuasca rituals. It draws on long-term fieldwork and participant observation in ayahuasca communities, and in-depth, semi-structured interviews of participants with histories of substance misuse. Ayahuasca's efficacy in the treatment of addiction blends somatic, symbolic and collective dimensions. The layering of these effects, and the direction given to them through ritual, circumscribes the experience and provides tools to render it meaningful. Prevailing modes of evaluation are ill suited to account for the particular material and semiotic efficacy of complex interventions such as ayahuasca healing for addiction. The article argues that practices of care characteristic of the ritual spaces in which ayahuasca is collectively consumed, play a key therapeutic role. The ritual use of ayahuasca stands in strong contrast to hegemonic understandings of addiction, paving new ground between the overstated difference between community and pharmacological interventions. The article concludes that fluid, adaptable forms of caregiving play a key role in the success of addiction recovery and that feeling part of a community has an important therapeutic potential. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  20. Considerations for effusive cryovolcanism on Europa: The post-Galileo perspective

    NASA Astrophysics Data System (ADS)

    Fagents, Sarah A.

    2003-12-01

    Cryovolcanic resurfacing is a popular mechanism to explain relatively young surface units on icy satellites of Jupiter, Saturn, Uranus, and Neptune. Prior to the Galileo data acquired between 1996 and 2001, Europa was thought to have undergone significant cryovolcanic resurfacing, facilitated by a global ocean beneath the icy surface. However, close examination of Galileo data at resolutions much better than those of Voyager images show that many of the features previously thought to be cryovolcanic are commonly best explained by other formative mechanisms, including tectonism and diapirism. In this study, I present an examination of the characteristics of a variety of Europan surface features for which effusive cryovolcanism is a possible origin, including apparently lobate ``flows,'' certain elliptical to circular lenticulae, and low-lying, smooth, low-albedo surfaces. A review of cryovolcanic eruption theory, together with Galileo data analysis of Europan surface geology and composition, indicates that cryovolcanism is a viable, though not unequivocal, explanation for some of these features. Some constraints on cryomagma properties and lithospheric structure are offered for these cases. The presence of small-volume, low-viscosity effusions is supported by observations and modeling. Some positive relief lenticulae could represent more viscous effusions, although diapirism may be a preferable explanation. However, strong evidence is lacking for cryovolcanic resurfacing on a large scale. On the basis of our experience with Galileo images of Europa (and Ganymede), Voyager-era inferences for widespread cryovolcanism on icy satellites may be overstated and will need to be carefully reexamined in the light of new data from upcoming spacecraft missions.

  1. Overstated evidence for short-term effects of violent games on affect and behavior: A reanalysis of Anderson et al. (2010).

    PubMed

    Hilgard, Joseph; Engelhardt, Christopher R; Rouder, Jeffrey N

    2017-07-01

    Violent video games are theorized to be a significant cause of aggressive thoughts, feelings, and behaviors. Important evidence for this claim comes from a large meta-analysis by Anderson and colleagues (2010), who found effects of violent games in experimental, cross-sectional, and longitudinal research. In that meta-analysis, the authors argued that there is little publication or analytic bias in the literature, an argument supported by their use of the trim-and-fill procedure. In the present manuscript, we reexamine their meta-analysis using a wider array of techniques for detecting bias and adjusting effect sizes. Our conclusions differ from those of Anderson and colleagues in 3 salient ways. First, we detect substantial publication bias in experimental research on the effects of violent games on aggressive affect and aggressive behavior. Second, after adjustment for bias, the effects of violent games on aggressive behavior in experimental research are estimated as being very small, and estimates of effects on aggressive affect are much reduced. In contrast, the cross-sectional literature finds correlations that appear largely unbiased. Third, experiments meeting the original authors' criteria for methodological quality do not yield larger adjusted effects than other experiments, but instead yield larger indications of bias, indicating that perhaps they were selected for significance. We outline future directions for stronger experimental research. The results indicate the need for an open, transparent, and preregistered research process to test the existence of the basic phenomenon. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  2. Layering garments during rest and exercise in the cold (8°C): wearer responses and comparability with selected fabric properties.

    PubMed

    MacRae, Braid A; Laing, Raechel M; Wilson, Cheryl A; Niven, Brian E

    2014-01-01

    How garments contribute to performance of the clothing system during wear is of interest, as is understanding the value of using fabric properties to inform end-use characteristics. To investigate the influences of layering upper-body garments, four fabrics were used to construct two first-layer garments (wool and polyester) and two outer-layer garments (wool and membrane laminate). Over six sessions, 10 moderately trained males wore each first-layer garment as a single layer and in combination with each outer-layer garment while resting, running and walking in cold environmental conditions (8 ± 1°C, 81 ± 4% RH). Here, the type of garment arrangement worn (fabric type or number of layers) had little influence on heart rate, core body temperature and change in body mass. Weighted mean covered skin temperature was warmer and weighted mean next-to-skin vapour pressure was typically higher (following the onset of exercise) with two layers versus one. Differences among fabrics for individual properties were typically overstated compared to differences among corresponding garments for physiological and psychophysical variables under the conditions of this study. These findings inform the interpretation of particular fabric properties and highlight issues to be acknowledged during development/refinement of fabric test methods. We examined the way in which selected fibre, fabric and garment (layering) characteristics contribute to performance of the clothing system during wear under cold conditions. Selected properties of the constituent fabrics were found to provide limited insight into how garments perform during wear under the conditions of this study.

  3. Staff satisfaction and retention and the role of the nursing unit manager.

    PubMed

    Duffield, Christine; Roche, Michael; O'Brien-Pallas, Linda; Catling-Paull, Christine; King, Madeleine

    2009-01-01

    Despite recent increases in nursing recruitment in Australia, participation in the workforce is still below the numbers predicted to meet future needs. This paper discusses factors impacting on nurses' job satisfaction, satisfaction with nursing and intention to leave in public sector hospitals in New South Wales (NSW), Australia. Staffing and patient data were collected on 80 medical and surgical units during 2004/5. This included a wide range of individual nurse data from a Nurse Survey; detailed and comprehensive staffing data including skill mix variables; patient characteristics; workload data; a profile of the ward's characteristics; and adverse event patient data. Nurses who were intending to remain in their job were more likely to be satisfied, be older, and have dependents. They were also likely to be experiencing good leadership and to have allied health support on the ward. Most nurses reported being satisfied with their profession, while a lower proportion reported satisfaction with their current position. Work environment factors such as nurses' autonomy, control over their practice and nursing leadership on the ward were statistically significant predictors of job satisfaction. This study will inform decision-making and policy for managers in both the public and private hospital sectors. This is the first large study which explored the work environment at the ward/unit level in public hospitals in NSW (Australia). It illustrates that there are no typical wards; each ward functions differently. The importance of nursing leadership at the ward level to job satisfaction, satisfaction with nursing and intention to leave, cannot be overstated.

  4. Reproducibility in Psychological Science: When Do Psychological Phenomena Exist?

    PubMed Central

    Iso-Ahola, Seppo E.

    2017-01-01

    Scientific evidence has recently been used to assert that certain psychological phenomena do not exist. Such claims, however, cannot be made because (1) scientific method itself is seriously limited (i.e., it can never prove a negative); (2) non-existence of phenomena would require a complete absence of both logical (theoretical) and empirical support; even if empirical support is weak, logical and theoretical support can be strong; (3) statistical data are only one piece of evidence and cannot be used to reduce psychological phenomena to statistical phenomena; and (4) psychological phenomena vary across time, situations and persons. The human mind is unreproducible from one situation to another. Psychological phenomena are not particles that can decisively be tested and discovered. Therefore, a declaration that a phenomenon is not real is not only theoretically and empirically unjustified but runs counter to the propositional and provisional nature of scientific knowledge. There are only “temporary winners” and no “final truths” in scientific knowledge. Psychology is a science of subtleties in human affect, cognition and behavior. Its phenomena fluctuate with conditions and may sometimes be difficult to detect and reproduce empirically. When strictly applied, reproducibility is an overstated and even questionable concept in psychological science. Furthermore, statistical measures (e.g., effect size) are poor indicators of the theoretical importance and relevance of phenomena (cf. “deliberate practice” vs. “talent” in expert performance), not to mention whether phenomena are real or unreal. To better understand psychological phenomena, their theoretical and empirical properties should be examined via multiple parameters and criteria. Ten such parameters are suggested. PMID:28626435

  5. War Neuroses and Arthur Hurst: A Pioneering Medical Film about the Treatment of Psychiatric Battle Casualties

    PubMed Central

    Jones, Edgar

    2016-01-01

    From 1917 to 1918, Major Arthur Hurst filmed shell-shocked patients home from the war in France. Funded by the Medical Research Committee, and using Pathé cameramen, he recorded soldiers who suffered from intractable movement disorders as they underwent treatment at the Royal Victoria Hospital in Netley and undertook programs of occupational therapy at Seale Hayne in Devon. As one of the earliest UK medical films, Hurst’s efforts may have drawn inspiration from the official documentary of the Battle of the Somme and films made in 1916 by French Army neurologists. Although initially motivated to make use of a novel medium to illustrate lectures, Hurst was alert to the wider appeal of the motion picture and saw an opportunity to position himself in the postwar medical hierarchy. Some “before treatment” shots were reenacted for the camera. Hurst, like some other shell shock doctors, openly used deception as a therapeutic measure. On the basis that the ends justified the means, they defended this procedure as ethical. Clinicians also took advantage of changes in military regulations to address functional symptoms. Claims made of “cures” in the film and associated publications by Hurst were challenged by other doctors treating shell shock. The absence of follow-up data and evidence from war pension files suggested that Hurst may have overstated the effectiveness of his methods. Nevertheless, the message conveyed in the film that chronic cases could be treated in a single session had a powerful resonance for ambitious or charismatic doctors and was revived in World War II. PMID:21596724

  6. West African monsoon dynamics inferred from abrupt fluctuations of Lake Mega-Chad

    PubMed Central

    Armitage, Simon J.; Bristow, Charlie S.; Drake, Nick A.

    2015-01-01

    From the deglacial period to the mid-Holocene, North Africa was characterized by much wetter conditions than today. The broad timing of this period, termed the African Humid Period, is well known. However, the rapidity of the onset and termination of the African Humid Period are contested, with strong evidence for both abrupt and gradual change. We use optically stimulated luminescence dating of dunes, shorelines, and fluviolacustrine deposits to reconstruct the fluctuations of Lake Mega-Chad, which was the largest pluvial lake in Africa. Humid conditions first occur at ∼15 ka, and by 11.5 ka, Lake Mega-Chad had reached a highstand, which persisted until 5.0 ka. Lake levels fell rapidly at ∼5 ka, indicating abrupt aridification across the entire Lake Mega-Chad Basin. This record provides strong terrestrial evidence that the African Humid Period ended abruptly, supporting the hypothesis that the African monsoon responds to insolation forcing in a markedly nonlinear manner. In addition, Lake Mega-Chad exerts strong control on global biogeochemical cycles because the northern (Bodélé) basin is currently the world’s greatest single dust source and possibly an important source of limiting nutrients for both the Amazon Basin and equatorial Atlantic. However, we demonstrate that the final desiccation of the Bodélé Basin occurred around 1 ka. Consequently, the present-day mode and scale of dust production from the Bodélé Basin cannot have occurred before 1 ka, suggesting that its role in fertilizing marine and terrestrial ecosystems is either overstated or geologically recent. PMID:26124133

  7. International variation in absence from work attributed to musculoskeletal illness: findings from the CUPID study.

    PubMed

    Coggon, David; Ntani, Georgia; Vargas-Prada, Sergio; Martinez, José Miguel; Serra, Consol; Benavides, Fernando G; Palmer, Keith T

    2013-08-01

    To quantify the variation in rates of absence due to musculoskeletal pain across 47 occupational groups (mostly nurses and office workers) from 18 countries, and to explore personal and group-level risk factors that might explain observed differences. A standardised questionnaire was used to obtain information about musculoskeletal pain, sickness absence and possible risk factors in a cross-sectional survey of 12 416 workers (92-1017 per occupational group). Additionally, group-level data on socioeconomic variables, such as sick pay and unemployment rates, were assembled by members of the study team in each country. Associations of sickness absence with risk factors were examined by Poisson regression. Overall, there were more than 30-fold differences between occupational groups in the 12-month prevalence of prolonged musculoskeletal sickness absence, and even among office workers carrying out similar occupational tasks, the variation was more than tenfold. Personal risk factors included older age, lower educational level, tendency to somatise, physical loading at work and prolonged absence for non-musculoskeletal illness. However, these explained little of the variation between occupational groups. After adjustment for individual characteristics, prolonged musculoskeletal sickness absence was more frequent in groups with greater time pressure at work, lower job control and more adverse beliefs about the work-relatedness of musculoskeletal disorders. Musculoskeletal sickness absence might be reduced by eliminating excessive time pressures in work, maximising employees' responsibility and control and providing flexibility of duties for those with disabling symptoms. Care should be taken not to overstate work as a cause of musculoskeletal injury.

  8. Experimental study of Fe-Mg- and Ca-distribution between coexisting ortho- and clinopyroxenes at P=294 MPa, T=750 and 800° C

    NASA Astrophysics Data System (ADS)

    Fonarev, V. I.; Graphchikov, A. A.

    1982-07-01

    The Fe-Mg-Ca-distribution was investigated in synthesis experiments and with the mineral assemblage orthopyroxene+clinopyroxene+quartz. The phase compositions were identified by X-ray diffraction and, where possible, by electron microprobe. The attainment of equilibrium in the run products was signalled by the compositions from control runs (different solutions) becoming closely similar, by recycling runs, by the attainment of equilibrium from different directions (depending on the composition of starting phases), and by special kinetic experiments. The study produced the following results: (1) the Ca content of the clinopyroxenes decreases with increasing Fe (mol%) from 48.4 at X {Cpx/Fe}=5 to 39.8 at X {Cpx/Fe}=45 (800° C); from 47.6 at X {Cpx/Fe}= 10 to 41.7 at X {Cpx/Fe}=45 (750° C); increasing temperature expands the stability field of the less calcic clinopyroxenes. (2) The Ca content of orthopyroxenes increases slightly with Fe content from 1.8 at X {Opx/Fe}=20.5 to 3.2 at X {Opx/Fe}=75; the temperature effect on the Ca content under the T, P conditions of the experiment was not large. (3) Fe and Mg distribution between the coexisting ortho-and clinopyroxenes is largely temperature-dependent, particularly in the compositional range X {Opx/Fe}=15 75 mol%; as T increases, Fe redistributes from the rhombic to monoclinic mineral. Preliminary estimates of rock formation temperatures using the obtained data show that most of the known two-pyroxene geothermometers overstate the actual values by 50 150° C.

  9. Longitudinal study of household smoking ban adoption among Korean Americans.

    PubMed

    Hughes, Suzanne C; Corcos, Isabel A; Hofstetter, C Richard; Hovell, Melbourne F; Irvin, Veronica L

    2009-11-01

    Few longitudinal studies have examined the adoption of bans on smoking in private homes. This longitudinal study examined: (1) the prevalence of home smoking bans at baseline, (2) the incidence and predictors of new ban implementation by follow-up, and (3) the reasons for banning smoking and the difficulties with enforcement. The sample consisted of 1360 adults of Korean descent residing in California who were interviewed by telephone (in English/Korean) at baseline during 2001-2002 and re-interviewed in 2006-2007. Data analyses were conducted in 2007-2008. The proportion of respondents with a complete household smoking ban grew from 59% at baseline to 91% by the follow-up interview. Among the 552 respondents who did not have a ban at baseline, 84% had adopted a ban by follow-up. Three baseline factors independently predicted ban adoption during the follow-up period: the presence of a nonsmoking respondent or spouse, the presence of nonsmoking family members, and respondent's belief that secondhand smoke caused lung cancer. The most highly rated reasons for banning smoking were as follows: because smoke annoys others, to protect family members, to avoid the odor, to discourage youth from smoking, and to encourage smokers to quit. Finally, respondents indicated that they would find it most difficult to ask their parent-in-law not to smoke. The proportion of households with smoking bans increased substantially, but households with smokers or family members who smoke remained less likely to implement bans. The importance of culturally sensitive programs to promote household bans cannot be overstated.

  10. Do water-saving technologies improve environmental flows?

    NASA Astrophysics Data System (ADS)

    Batchelor, Charles; Reddy, V. Ratna; Linstead, Conor; Dhar, Murli; Roy, Sumit; May, Rebecca

    2014-10-01

    Water saving and conservation technologies (WCTs) have been promoted widely in India as a practical means of improving the water use efficiency and freeing up water for other uses (e.g. for maintaining environmental flows in river systems). However, there is increasing evidence that, somewhat paradoxically, WCTs often contribute to intensification of water use by irrigated and rainfed farming systems. This occurs when: (1) Increased crop yields are coupled with increased consumptive water use and/or (2) Improved efficiency, productivity and profitability encourages farmers to increase the area cropped and/or to adopt multiple cropping systems. In both cases, the net effect is an increase in annual evapotranspiration that, particularly in areas of increasing water scarcity, can have the trade-off of reduced environmental flows. Recognition is also increasing that the claimed water savings of many WCTs may have been overstated. The root cause of this problem lies in confusion over what constitutes real water saving at the system or basin scales. The simple fact is that some of the water that is claimed to be ‘saved’ by WCTs would have percolated into the groundwater from where it can be and often is accessed and reused. Similarly, some of the “saved” runoff can be used downstream by, for example, farmers or freshwater ecosystems. This paper concludes that, particularly in areas facing increasing water scarcity, environmental flows will only be restored and maintained if they are given explicit (rather than theoretical or notional) attention. With this in mind, a simple methodology is proposed for deciding when and where WCTs may have detrimental impacts on environmental flows.

  11. Potential effects of gas hydrate on human welfare

    PubMed Central

    Kvenvolden, Keith A.

    1999-01-01

    For almost 30 years. serious interest has been directed toward natural gas hydrate, a crystalline solid composed of water and methane, as a potential (i) energy resource, (ii) factor in global climate change, and (iii) submarine geohazard. Although each of these issues can affect human welfare, only (iii) is considered to be of immediate importance. Assessments of gas hydrate as an energy resource have often been overly optimistic, based in part on its very high methane content and on its worldwide occurrence in continental margins. Although these attributes are attractive, geologic settings, reservoir properties, and phase-equilibria considerations diminish the energy resource potential of natural gas hydrate. The possible role of gas hydrate in global climate change has been often overstated. Although methane is a “greenhouse” gas in the atmosphere, much methane from dissociated gas hydrate may never reach the atmosphere, but rather may be converted to carbon dioxide and sequestered by the hydrosphere/biosphere before reaching the atmosphere. Thus, methane from gas hydrate may have little opportunity to affect global climate change. However, submarine geohazards (such as sediment instabilities and slope failures on local and regional scales, leading to debris flows, slumps, slides, and possible tsunamis) caused by gas-hydrate dissociation are of immediate and increasing importance as humankind moves to exploit seabed resources in ever-deepening waters of coastal oceans. The vulnerability of gas hydrate to temperature and sea level changes enhances the instability of deep-water oceanic sediments, and thus human activities and installations in this setting can be affected. PMID:10097052

  12. Comment on 'Modeling of Convective-Stratiform Precipitation Processes: Sensitivity to Partitioning Methods' by Matthias Steiner

    NASA Technical Reports Server (NTRS)

    Lang, Steve; Tao, W.-K.; Simpson, J.; Ferrier, B.

    2003-01-01

    Despite the obvious notion that the presence of hail or graupel is a good indication of convection, the model results show this does not provide an objective benchmark partly due to the unrealistic presence of small amounts of hail or graupel throughout the anvil in the model but mainly because of the significant amounts of hail or graupel, especially in the tropical TOGA COARE simulation, in the transition zone. Without use of a "transition" category, it is open to debate as how this region should best be defined, as stratiform or as convective. So, the presence of significant hail or graupel contents in this zone significantly degrades its use an objective benchmark for convection. The separation algorithm comparison was done in the context of a cloud-resolving model. These models are widely used and serve a variety of purposes especially with regard to retrieving information that cannot be directly measured by providing synthetic data sets that are consistent and complete. Separation algorithms are regularly applied in these models. However, as with any modeling system, these types 'of models are constantly being improved to overcome any known deficiencies and make them more accurate representations of observed systems. The presence of hail and graupel in the anvil and the bias towards heavy rainfall rates are two such examples of areas that need improvement. Since, both of these can effect the perceived performance of the separation algorithms, the Lang et al. (2003) study did not want to overstate the relative performance of any specific algorithms.

  13. African American race and HIV virological suppression: beyond disparities in clinic attendance.

    PubMed

    Howe, Chanelle J; Napravnik, Sonia; Cole, Stephen R; Kaufman, Jay S; Adimora, Adaora A; Elston, Beth; Eron, Joseph J; Mugavero, Michael J

    2014-06-15

    Racial disparities in clinic attendance may contribute to racial disparities in plasma human immunodeficiency virus type 1 : HIV-1) RNA levels among HIV-positive patients in care. Data from 946 African American and 535 Caucasian patients receiving HIV care at the University of North Carolina Center for AIDS Research HIV clinic between January 1, 1999, and August 1, 2012, were used to estimate the association between African American race and HIV virological suppression (i.e., undetectable HIV-1 RNA) when racial disparities in clinic attendance were lessened. Clinic attendance was measured as the proportion of scheduled clinic appointments attended (i.e., visit adherence) or the proportion of six 4-month intervals with at least 1 attended scheduled clinic appointment (i.e., visit constancy). In analyses accounting for patient characteristics, the risk ratio for achieving suppression when comparing African Americans with Caucasians was 0.91 (95% confidence interval: 0.85, 0.98). Lessening disparities in adherence or constancy lowered disparities in virological suppression by up to 44.4% and 11.1%, respectively. Interventions that lessen disparities in adherence may be more effective in eliminating disparities in suppression than interventions that lessen disparities in constancy. Given that gaps in care were limited to be no more than 2 years for both attendance measures, the impact of lessening disparities in adherence may be overstated. © The Author 2014. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. The role of the principle of double effect in ethics education at US medical schools and its potential impact on pain management at the end of life.

    PubMed

    Macauley, Robert

    2012-03-01

    Because opioids can suppress respiratory drive, the principle of double effect (PDE) has been used to justify their use for terminally ill patients. Recent studies, however, suggest that the risk of respiratory depression in typical end-of-life (EOL) situations may be overstated and that heightened concern for this rare occurrence can lead to inadequate treatment of pain. The purpose of this study is to examine the role of the PDE in medical school ethics education, with specific reference to its potential impact on pain management at EOL. After obtaining institutional review board approval, an electronic survey was sent to ethics educators at every allopathic medical school in the USA. One-third of ethics educators felt that opioids were 'likely' to cause significant respiratory depression that could hasten death. Educators' opinions of opioid effects did not influence their view of the relevance of the PDE, with approximately 70% deeming it relevant to EOL care. Only 15% of ethics educators believed that associating the PDE with opioid use might discourage clinicians from optimally treating pain, out of concern for respiratory depression. This study demonstrates that a significant minority of ethics educators believe, contrary to current evidence, that opioids are 'likely' to cause significant respiratory depression that could hasten death in terminally ill patients. Yet, many of those who do not feel this is likely still rely on the PDE to justify this possibility, potentially (and unknowingly) contributing to clinical misperceptions and underutilisation of opioids at EOL.

  15. War neuroses and Arthur Hurst: a pioneering medical film about the treatment of psychiatric battle casualties.

    PubMed

    Jones, Edgar

    2012-07-01

    From 1917 to 1918, Major Arthur Hurst filmed shell-shocked patients home from the war in France. Funded by the Medical Research Committee, and using Pathé cameramen, he recorded soldiers who suffered from intractable movement disorders as they underwent treatment at the Royal Victoria Hospital in Netley and undertook programs of occupational therapy at Seale Hayne in Devon. As one of the earliest UK medical films, Hurst's efforts may have drawn inspiration from the official documentary of the Battle of the Somme and films made in 1916 by French Army neurologists. Although initially motivated to make use of a novel medium to illustrate lectures, Hurst was alert to the wider appeal of the motion picture and saw an opportunity to position himself in the postwar medical hierarchy. Some "before treatment" shots were reenacted for the camera. Hurst, like some other shell shock doctors, openly used deception as a therapeutic measure. On the basis that the ends justified the means, they defended this procedure as ethical. Clinicians also took advantage of changes in military regulations to address functional symptoms. Claims made of "cures" in the film and associated publications by Hurst were challenged by other doctors treating shell shock. The absence of follow-up data and evidence from war pension files suggested that Hurst may have overstated the effectiveness of his methods. Nevertheless, the message conveyed in the film that chronic cases could be treated in a single session had a powerful resonance for ambitious or charismatic doctors and was revived in World War II.

  16. Labor market productivity costs for caregivers of children with spina bifida: a population-based analysis.

    PubMed

    Tilford, John M; Grosse, Scott D; Goodman, Allen C; Li, Kemeng

    2009-01-01

    Caregiver productivity costs are an important component of the overall cost of care for individuals with birth defects and developmental disabilities, yet few studies provide estimates for use in economic evaluations. This study estimates labor market productivity costs for caregivers of children and adolescents with spina bifida. Case families were recruited from a state birth defects registry in Arkansas. Primary caregivers of children with spina bifida (N = 98) reported their employment status in the past year and demographic characteristics. Controls were abstracted from the Current Population Survey covering the state of Arkansas for the same time period (N = 416). Estimates from regression analyses of labor market outcomes were used to calculate differences in hours worked per week and lifetime costs. Caregivers of children with spina bifida worked an annual average of 7.5 to 11.3 hours less per week depending on the disability severity. Differences in work hours by caregivers of children with spina bifida translated into lifetime costs of $133,755 in 2002 dollars using a 3% discount rate and an age- and sex-adjusted earnings profile. Including caregivers' labor market productivity costs in prevention effectiveness estimates raises the net cost savings per averted case of spina bifida by 48% over the medical care costs alone. Information on labor market productivity costs for caregivers can be used to better inform economic evaluations of prevention and treatment strategies for spina bifida. Cost-effectiveness calculations that omit caregiver productivity costs substantially overstate the net costs of the intervention and underestimate societal value.

  17. The ethics and politics of mindfulness-based interventions.

    PubMed

    Schmidt, Andreas T

    2016-07-01

    Recently, there has been a lot of enthusiasm for mindfulness practice and its use in healthcare, businesses and schools. An increasing number of studies give us ground for cautious optimism about the potential of mindfulness-based interventions (MBIs) to improve people's lives across a number of dimensions. This paper identifies and addresses some of the main ethical and political questions for larger-scale MBIs. First, how far are MBIs compatible with liberal neutrality given the great diversity of lifestyles and conceptions of the good characteristic of modern societies? It will be argued that the potential benefits of contemporary secular mindfulness practice are indeed of a sufficiently primary or all-purpose nature to qualify as suitable goals of liberal public policy. Second, what challenges are brought up if mindfulness is used in contexts and applications-such as military settings-whose goals seem incompatible with the ethical and soteriological views of traditional mindfulness practice? It will be argued that, given concerns regarding liberal neutrality and reasonable disagreement about ethics, MBIs should avoid strong ethical commitments. Therefore, it should, in principle, be applicable in contexts of controversial moral value. Finally, drawing on recent discussions within the mindfulness community, it is argued that we should not overstate the case for mindfulness and not crowd out discussion of organisational and social determinants of stress, lowered well-being, and mental illness and the collective measures necessary to address them. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  18. Tobacco industry interference with tobacco control policies in Poland: legal aspects and industry practices

    PubMed Central

    Balwicki, Łukasz; Stokłosa, Michał; Balwicka-Szczyrba, Małgorzata; Tomczak, Wioleta

    2016-01-01

    Background Since 2006, when Poland ratified the WHO Framework Convention on Tobacco Control (FCTC), there have been efforts to improve tobacco control regulation in the country. At the same time, at the European Union level, Poland took part in discussions over revision of the Tobacco Tax Directive and the Tobacco Products Directive. This study aims to explore the tobacco industry's tactics to interfere with the creation of those policies. Methods Analysis of 257 documents obtained through freedom of information request. Results We identified three means that the tobacco industry used to interfere with tobacco control policies: creating a positive attitude, expressing a will to be a part of the policymaking process, and exerting pressure. We found that those tactics have often been used unethically, with the industry providing the government with ready legislation proposals, overstating its contribution to the economy and the government revenues, misrepresenting the illicit cigarette problem and misusing scientific evidence. The industry also used legal threats, including use of bilateral trade agreements, against implementation of tobacco control measures. The companies lobbied together directly and through third parties, with the cigarette excise tax structure being the only area of disagreement among the companies. The industry also pushed the Polish government to challenge tobacco control policies in countries with stronger public policy standards, including UK display bans and the Australian plain-packaging law. Conclusions From an object of regulation, the tobacco industry in Poland became a partner with the government in legislative work. Implementation of provisions of Article 5.3 of the WHO FCTC could prevent further industry interference. PMID:26418616

  19. Do decision-analytic models identify cost-effective treatments? A retrospective look at helicobacter pylori eradication.

    PubMed

    Fairman, Kathleen A; Motheral, Brenda R

    2003-01-01

    Pharmacoeconomic models of Helicobacter (H) pylori eradication have been frequently cited but never validated. Examine retrospectively whether H pylori pharmacoeconomic models direct decision makers to cost-effective therapeutic choices. We first replicated and then validated 2 models, replacing model assumptions with empirical data from a multipayer claims database. Database subjects were 435 commercially insured U.S. patients treated with bismuthmetronidazole- tetracycline (BMT), proton pump inhibitor (PPI)-clarithromycin, or PPI-amoxicillin. Patients met >1 clinical requirement (ulcer disease, gastritis/duodenitis, stomach function disorder, abdominal pain, H pylori infection, endoscopy, or H pylori assay). Sensitivity analyses included only patients with ulcer diagnosis or gastrointestinal specialist care. Outcome measures were: (1) rates of eradication retreatment; (2) use of office visits, hospitalizations, endoscopies, and antisecretory medication; and (3) cost per effectively treated (nonretreated) patient. Model results overstated the cost-effectiveness of PPI-clarithromycin and underestimated the cost-effectiveness of BMT. Prior to empirical adjustment, costs per effectively treated patient were 1,001 US dollars, 980 US dollars, and 1,730 US dollars for BMT, PPIclarithromycin, and PPI-amoxicillin, respectively. Estimates after adjustment were US dollars for BMT, 1,118 US dollars for PPI-clarithromycin, and 1,131 US dollars for PPI-amoxicillin. Key model assumptions that proved retrospectively incorrect were largely unsupported by either empirical evidence or systematic assessment of expert opinion. Organizations with access to medical and pharmacy claims databases should test key assumptions of influential models to determine their validity. Journal peer-review processes should pay particular attention to the basis of model assumptions.

  20. Conceptualizing the impacts of dual practice on the retention of public sector specialists - evidence from South Africa.

    PubMed

    Ashmore, John; Gilson, Lucy

    2015-01-19

    'Dual practice', or multiple job holding, generally involves public sector-based health workers taking additional work in the private sector. This form of the practice is purported to help retain public health care workers in low and middle-income countries' public sectors through additional wage incentives. There has been little conceptual or empirical development of the relationship between dual practice and retention. This article helps begin to fill this gap, drawing on empirical evidence from a qualitative study focusing on South African specialists. Fifty-one repeat, in-depth interviews were carried out with 28 doctors (predominantly specialists) with more than one job, in one public and one private urban hospital. Findings suggest dual practice can impact both positively and negatively on specialists' intention to stay in the public sector. This is through multiple conceptual channels including those previously identified in the literature such as dual practice acting as a 'stepping stone' to private practice by reducing migration costs. Dual practice can also lead specialists to re-evaluate how they compare public and private jobs, and to overworking which can expedite decisions on whether to stay in the public sector or leave. Numerous respondents undertook dual practice without official permission. The idea that dual practice helps retain public specialists in South Africa may be overstated. Yet banning the practice may be ineffective, given many undertake it without permission in any case. Regulation should be better enforced to ensure dual practice is not abused. The conceptual framework developed in this article could form a basis for further qualitative and quantitative inquiry.

  1. Proper interpretation of chronic toxicity studies and their statistics: A critique of "Which level of evidence does the US National Toxicology Program provide? Statistical considerations using the Technical Report 578 on Ginkgo biloba as an example".

    PubMed

    Kissling, Grace E; Haseman, Joseph K; Zeiger, Errol

    2015-09-02

    A recent article by Gaus (2014) demonstrates a serious misunderstanding of the NTP's statistical analysis and interpretation of rodent carcinogenicity data as reported in Technical Report 578 (Ginkgo biloba) (NTP, 2013), as well as a failure to acknowledge the abundant literature on false positive rates in rodent carcinogenicity studies. The NTP reported Ginkgo biloba extract to be carcinogenic in mice and rats. Gaus claims that, in this study, 4800 statistical comparisons were possible, and that 209 of them were statistically significant (p<0.05) compared with 240 (4800×0.05) expected by chance alone; thus, the carcinogenicity of Ginkgo biloba extract cannot be definitively established. However, his assumptions and calculations are flawed since he incorrectly assumes that the NTP uses no correction for multiple comparisons, and that significance tests for discrete data operate at exactly the nominal level. He also misrepresents the NTP's decision making process, overstates the number of statistical comparisons made, and ignores the fact that the mouse liver tumor effects were so striking (e.g., p<0.0000000000001) that it is virtually impossible that they could be false positive outcomes. Gaus' conclusion that such obvious responses merely "generate a hypothesis" rather than demonstrate a real carcinogenic effect has no scientific credibility. Moreover, his claims regarding the high frequency of false positive outcomes in carcinogenicity studies are misleading because of his methodological misconceptions and errors. Published by Elsevier Ireland Ltd.

  2. Drug breakthrough offers hope to arthritis sufferers: qualitative analysis of medical research in UK newspapers.

    PubMed

    Hanson, Helen; O'Brien, Nicola; Whybrow, Paul; Isaacs, John D; Rapley, Tim

    2017-04-01

    Newspaper stories can impact behaviours, particularly in relation to research participation. It is therefore important to understand the narratives presented and ways in which these are received. Some work to date assumes journalism transmits existing medical knowledge to a passive audience. This study aimed to explore how newspaper articles present stories about medical research and how people interpret and use them. Qualitative research methods were employed to analyse two data sets: newspaper articles relating to 'rheumatoid arthritis' and 'research' from UK local and national news sources; and existing transcripts of interviews with patients with rheumatoid arthritis and their carers. Newspapers present a positive account of medical research, through a simple narrative with three essential components: an 'innovation' offers 'hope' in the context of 'burden'. Patients frequently feature as passive subjects without attributed opinions. Few articles include patients' experiences of research involvement. Patients with rheumatoid arthritis and their carers read articles about medical research critically, often with cynicism and drawing on other sources for interpretation. An understanding of the simple, positive narrative of medical research found in newspaper articles may enable researchers to gain mass media exposure for their work and challenge this typical style of reporting. The critical and cynical ways patients and carers read stories about medical research suggest that concerns about newspaper articles misinforming the public may be overstated, but any effect on research engagement is unknown. Newspaper articles rarely present patients' views or their experiences of research, and this can be conceptualized as 'depersonalization bias'. © 2016 The Authors. Health Expectations Published by John Wiley & Sons Ltd.

  3. AOD treatment agencies: does religious affiliation influence service delivery?

    PubMed

    McIlwraith, Fairlie; Kinner, Stuart A; Najman, Jake M

    2011-11-01

    Religious organisations have been involved in delivering alcohol and other drug (AOD) services since Australian colonial times and are a familiar presence in the AOD sector. However, there is concern in some sectors that AOD services delivered by religious organisations might be influenced by religious ideology, at the expense of evidence-based service provision. A national, cross-sectional survey of non-government AOD agencies was undertaken using a mailed questionnaire. All non-government AOD agencies in Australia, providing at least one face-to-face specialist AOD service, were invited to participate. Agency goals and activities were assessed using the Drug and Alcohol Program Treatment Inventory, which has eight distinct treatment orientations: 12-step, therapeutic community, cognitive behavioural therapy, psychodynamic, family, rehabilitation, dual diagnosis and medical. There was a high degree of uniformity in treatment orientations with religiously affiliated agencies having similar goals and activities to non-religiously affiliated agencies. Cognitive behavioural therapy was most commonly provided and 12-step the least provided. Religiously affiliated agencies were significantly more likely to favour the 12-step orientation in both goals and activities. Concerns that the religious affiliation of non-government organisations might influence AOD service delivery in Australia appear to be overstated. Factors contributing to the observed uniformity of care may include a more strategic, federal approach; and an increasing emphasis on best practice within the sector. The lack of discernable differentiation between religiously affiliated and non-religiously affiliated non-government organisations may also be attributable to changes in the way services are delivered by many religious organisations. © 2011 Australasian Professional Society on Alcohol and other Drugs.

  4. Reporting of Positive Results in Randomized Controlled Trials of Mindfulness-Based Mental Health Interventions.

    PubMed

    Coronado-Montoya, Stephanie; Levis, Alexander W; Kwakkenbos, Linda; Steele, Russell J; Turner, Erick H; Thombs, Brett D

    2016-01-01

    A large proportion of mindfulness-based therapy trials report statistically significant results, even in the context of very low statistical power. The objective of the present study was to characterize the reporting of "positive" results in randomized controlled trials of mindfulness-based therapy. We also assessed mindfulness-based therapy trial registrations for indications of possible reporting bias and reviewed recent systematic reviews and meta-analyses to determine whether reporting biases were identified. CINAHL, Cochrane CENTRAL, EMBASE, ISI, MEDLINE, PsycInfo, and SCOPUS databases were searched for randomized controlled trials of mindfulness-based therapy. The number of positive trials was described and compared to the number that might be expected if mindfulness-based therapy were similarly effective compared to individual therapy for depression. Trial registries were searched for mindfulness-based therapy registrations. CINAHL, Cochrane CENTRAL, EMBASE, ISI, MEDLINE, PsycInfo, and SCOPUS were also searched for mindfulness-based therapy systematic reviews and meta-analyses. 108 (87%) of 124 published trials reported ≥1 positive outcome in the abstract, and 109 (88%) concluded that mindfulness-based therapy was effective, 1.6 times greater than the expected number of positive trials based on effect size d = 0.55 (expected number positive trials = 65.7). Of 21 trial registrations, 13 (62%) remained unpublished 30 months post-trial completion. No trial registrations adequately specified a single primary outcome measure with time of assessment. None of 36 systematic reviews and meta-analyses concluded that effect estimates were overestimated due to reporting biases. The proportion of mindfulness-based therapy trials with statistically significant results may overstate what would occur in practice.

  5. Effects of a Malpractice Crisis on Specialist Supply and Patient Access to Care

    PubMed Central

    Mello, Michelle M.; Studdert, David M.; DesRoches, Catherine M.; Peugh, Jordon; Zapert, Kinga; Brennan, Troyen A.; Sage, William M.

    2005-01-01

    Objective: To investigate specialist physicians' practice decisions in response to liability concerns and their perceptions of the impact of the malpractice environment on patient access to care. Summary Background Data: A perennial concern during “malpractice crises” is that liability costs will drive physicians in high-risk specialties out of practice, creating specialist shortages and access-to-care problems. Methods: Mail survey of 824 Pennsylvania physicians in general surgery, neurosurgery, orthopedic surgery, obstetrics/gynecology, emergency medicine, and radiology eliciting information on practice decisions made in response to rising liability costs. Results: Strong majorities of specialists reported increases over the last 3 years in patients' driving distances (58%) and waiting times (83%) for specialist care or surgery, waiting times for emergency department care (82%), and the number of patients forced to switch physicians (89%). Professional liability costs and managed care were both considered important contributing factors. Small proportions of specialists reported that they would definitely retire (7%) or relocate their practice out of state (4%) within the next 2 years; another third (32% and 29%, respectively) said they would likely do so. Forty-two percent of specialists have reduced or eliminated high-risk aspects of their practice, and 50% are likely to do so over the next 2 years. Conclusions: Our data suggest that claims of a “physician exodus” from Pennsylvania due to rising liability costs are overstated, but the malpractice situation is having demonstrable effects on the supply of specialist physicians in affected areas and their scope of practice, which likely impinges upon patients' access to care. PMID:16244532

  6. Assessing stapes piston position using computed tomography: a cadaveric study.

    PubMed

    Hahn, Yoav; Diaz, Rodney; Hartman, Jonathan; Bobinski, Matthew; Brodie, Hilary

    2009-02-01

    Temporal bone computed tomographic (CT) scanning in the postoperative stapedotomy patient is inaccurate in assessing stapes piston position within the vestibule. Poststapedotomy patients that have persistent vertigo may undergo CT scanning to assess the position of the stapes piston within the vestibule to rule out overly deep insertion. Vertigo is a recognized complication of the deep piston, and CT evaluation is often recommended. The accuracy of CT scan in this setting is unestablished. Stapedotomy was performed on 12 cadaver ears, and stainless steel McGee pistons were placed. The cadaver heads were then scanned using a fine-cut temporal bone protocol. Temporal bone dissection was performed with microscopic measurement of the piston depth in the vestibule. These values were compared with depth of intravestibular penetration measured on CT scan by 4 independent measurements. The intravestibular penetration as assessed by computed tomography was consistently greater than the value found on cadaveric anatomic dissection. The radiographic bias was greater when piston location within the vestibule was shallower. The axial CT scan measurement was 0.53 mm greater, on average, than the anatomic measurement. On average, the coronal CT measurement was 0.68 mm greater than the anatomic measurement. The degree of overestimation of penetration, however, was highly inconsistent. Standard temporal bone CT scan is neither an accurate nor precise examination of stapes piston depth within the vestibule. We found that CT measurement consistently overstated intravestibular piston depth. Computed tomography is not a useful study in the evaluation of piston depth for poststapedectomy vertigo and is of limited value in this setting.

  7. Pharmacogenetics and the print media: what is the public told?

    PubMed

    Almomani, Basima; Hawwa, Ahmed F; Goodfellow, Nicola A; Millership, Jeffrey S; McElnay, James C

    2015-05-09

    Pharmacogenetics is a rapidly growing field that aims to identify the genes that influence drug response. This science can be used as a powerful tool to tailor drug treatment to the genetic makeup of individuals. The present study explores the coverage of the topic of pharmacogenetics and its potential benefit in personalised medicine by the UK newsprint media. The LexisNexis database was used to identify and retrieve full text articles from the 10 highest circulation national daily newspapers and their Sunday equivalents in the UK. Content analysis of newspaper articles which referenced pharmacogenetic testing was carried out. A second researcher coded a random sample (21%) of newspaper articles to establish the inter-rater reliability of coding. Of the 256 articles captured by the search terms, 96 articles (with pharmacogenetics as a major component) met the study inclusion criteria. The majority of articles over-stated the benefits of pharmacogenetic testing while paying less attention to the associated risks. Overall beneficial effects were mentioned 5.3 times more frequently than risks (p < 0.001). The most common illnesses for which pharmacogenetically based personalised medicine was discussed were cancer, cardiovascular disease and CNS diseases. Only 13% of newspaper articles that cited a specific scientific study mentioned this link in the article. There was a positive correlation between the size of the article and both the number of benefits and risks stated (P < 0.01). More comprehensive coverage of the area of personalised medicine within the print media is needed to inform public debate on the inclusion of pharmacogentic testing in routine practice.

  8. Evaluation of mucosal adjuvants and immunization routes for the induction of systemic and mucosal humoral immune responses in macaques.

    PubMed

    Veazey, Ronald S; Siddiqui, Asna; Klein, Katja; Buffa, Viviana; Fischetti, Lucia; Doyle-Meyers, Lara; King, Deborah F; Tregoning, John S; Shattock, Robin J

    2015-01-01

    Delivering vaccine antigens to mucosal surfaces is potentially very attractive, especially as protection from mucosal infections may be mediated by local immune responses. However, to date mucosal immunization has had limited successes, with issues of both safety and poor immunogenicity. One approach to improve immunogenicity is to develop adjuvants that are effective and safe at mucosal surfaces. Differences in immune responses between mice and men have overstated the value of some experimental adjuvants which have subsequently performed poorly in the clinic. Due to their closer similarity, non-human primates can provide a more accurate picture of adjuvant performance. In this study we immunised rhesus macaques (Macaca mulatta) using a unique matrix experimental design that maximised the number of adjuvants screened while reducing the animal usage. Macaques were immunised by the intranasal, sublingual and intrarectal routes with the model protein antigens keyhole limpet haemocyanin (KLH), β-galactosidase (β-Gal) and ovalbumin (OVA) in combination with the experimental adjuvants Poly(I:C), Pam3CSK4, chitosan, Thymic Stromal Lymphopoietin (TSLP), MPLA and R848 (Resiquimod). Of the routes used, only intranasal immunization with KLH and R848 induced a detectable antibody response. When compared to intramuscular immunization, intranasal administration gave slightly lower levels of antigen specific antibody in the plasma, but enhanced local responses. Following intranasal delivery of R848, we observed a mildly inflammatory response, but no difference to the control. From this we conclude that R848 is able to boost antibody responses to mucosally delivered antigen, without causing excess local inflammation.

  9. Using Caffeine Pills for Performance Enhancement. An Experimental Study on University Students’ Willingness and Their Intention to Try Neuroenhancements

    PubMed Central

    Brand, Ralf; Koch, Helen

    2016-01-01

    Recent research has indicated that university students sometimes use caffeine pills for neuroenhancement (NE; non-medical use of psychoactive substances or technology to produce a subjective enhancement in psychological functioning and experience), especially during exam preparation. In our factorial survey experiment, we manipulated the evidence participants were given about the prevalence of NE amongst peers and measured the resulting effects on the psychological predictors included in the Prototype-Willingness Model of risk behavior. Two hundred and thirty-one university students were randomized to a high prevalence condition (read faked research results overstating usage of caffeine pills amongst peers by a factor of 5; 50%), low prevalence condition (half the estimated prevalence; 5%) or control condition (no information about peer prevalence). Structural equation modeling confirmed that our participants’ willingness and intention to use caffeine pills in the next exam period could be explained by their past use of neuroenhancers, attitude to NE and subjective norm about use of caffeine pills whilst image of the typical user was a much less important factor. Provision of inaccurate information about prevalence reduced the predictive power of attitude with respect to willingness by 40-45%. This may be because receiving information about peer prevalence which does not fit with their perception of the social norm causes people to question their attitude. Prevalence information might exert a deterrent effect on NE via the attitude-willingness association. We argue that research into NE and deterrence of associated risk behaviors should be informed by psychological theory. PMID:26903909

  10. Observing Solar Eclipses in the Developing World

    NASA Astrophysics Data System (ADS)

    Pasachoff, J. M.

    2006-08-01

    The paths of totality of total solar eclipses cross the world, with each spot receiving such a view about every 300 years. The areas of the world from which partial eclipses are visible are much wider. For the few days prior to a total eclipse, the attention of a given country is often drawn toward the eclipse, providing a teachable moment that we can use to bring astronomy to the public's attention. Also, it is important to describe how to observe the partial phases of the eclipse safely. Further, it is important to describe to those people in the zone of totality that it is not only safe but also interesting to view totality. Those who are misled by false warnings that overstate the hazards of viewing the eclipse, or that fail to distinguish between safe and unsafe times for naked-eye viewing, may well be skeptical when other health warnings--perhaps about AIDS or malaria prevention or polio inoculations--come from the authorities, meaning that the penalties for misunderstanding the astronomical event can be severe. Through the International Astronomical Union's Working Group on Solar Eclipses and through the I.A.U.'s Program Group on Public Education at the Times of Eclipses, part of the Commission on Education and Development, we make available information to national authorities, to colleagues in the relevant countries, and to others, through our Websites at http://www.eclipses.info and http://www.totalsolareclipse.net and through personal communication. Among our successes at the 29 March 2006 total solar eclipse was the distribution through a colleague in Nigeria of 400,000 eye-protection filters.

  11. International variation in absence from work attributed to musculoskeletal illness: findings from the CUPID study

    PubMed Central

    Coggon, David; Ntani, Georgia; Vargas-Prada, Sergio; Martinez, José Miguel; Serra, Consol; Benavides, Fernando G; Palmer, Keith T

    2013-01-01

    Objectives To quantify the variation in rates of absence due to musculoskeletal pain across 47 occupational groups (mostly nurses and office workers) from 18 countries, and to explore personal and group-level risk factors that might explain observed differences. Methods A standardised questionnaire was used to obtain information about musculoskeletal pain, sickness absence and possible risk factors in a cross-sectional survey of 12 416 workers (92–1017 per occupational group). Additionally, group-level data on socioeconomic variables, such as sick pay and unemployment rates, were assembled by members of the study team in each country. Associations of sickness absence with risk factors were examined by Poisson regression. Results Overall, there were more than 30-fold differences between occupational groups in the 12-month prevalence of prolonged musculoskeletal sickness absence, and even among office workers carrying out similar occupational tasks, the variation was more than tenfold. Personal risk factors included older age, lower educational level, tendency to somatise, physical loading at work and prolonged absence for non-musculoskeletal illness. However, these explained little of the variation between occupational groups. After adjustment for individual characteristics, prolonged musculoskeletal sickness absence was more frequent in groups with greater time pressure at work, lower job control and more adverse beliefs about the work-relatedness of musculoskeletal disorders. Conclusions Musculoskeletal sickness absence might be reduced by eliminating excessive time pressures in work, maximising employees’ responsibility and control and providing flexibility of duties for those with disabling symptoms. Care should be taken not to overstate work as a cause of musculoskeletal injury. PMID:23695413

  12. Safety of Epinephrine in Digital Nerve Blocks: A Literature Review.

    PubMed

    Ilicki, Jonathan

    2015-11-01

    Digital nerve blocks are commonly performed in emergency departments. Health care practitioners are often taught to avoid performing blocks with epinephrine due to a risk of digital necrosis. To review the literature on the safety of epinephrine 1:100,000-200,000 (5-10 μg/mL) with local anesthetics in digital nerve blocks in healthy patients and in patients with risk for poor peripheral circulation. PubMed, Web of Science, and the Cochrane Library were searched in June 2014 using the query "digital block AND epinephrine OR digital block AND adrenaline". The searches were performed without any limits. Sixty-three articles were identified, and 39 of these were found to be relevant. These include nine reviews, 12 randomized control trials, and 18 other articles. Most studies excluded patients with risk for poor peripheral circulation. Two studies described using epinephrine on patients with vascular comorbidities. No study reported digital necrosis or gangrene attributable to epinephrine, either in healthy patients or in patients with risk for poor peripheral circulation. In total, at least 2797 digital nerve blocks with epinephrine have been performed without any complications. Epinephrine 1:100,000-200,000 (5-10 μg/mL) is safe to use in digital nerve blocks in healthy patients. Physiological studies show epinephrine-induced vasoconstriction to be transient. There are no reported cases of epinephrine-induced harm to patients with risk for poor peripheral circulation despite a theoretical risk of harmful epinephrine-induced vasoconstriction. A lack of reported complications suggests that the risk of epinephrine-induced vasoconstriction to digits may be overstated. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Proper interpretation of chronic toxicity studies and their statistics: A critique of “Which level of evidence does the US National Toxicology Program provide? Statistical considerations using the Technical Report 578 on Ginkgo biloba as an example”

    PubMed Central

    Kissling, Grace E.; Haseman, Joseph K.; Zeiger, Errol

    2014-01-01

    A recent article by Gaus (2014) demonstrates a serious misunderstanding of the NTP’s statistical analysis and interpretation of rodent carcinogenicity data as reported in Technical Report 578 (Ginkgo biloba) (NTP 2013), as well as a failure to acknowledge the abundant literature on false positive rates in rodent carcinogenicity studies. The NTP reported Ginkgo biloba extract to be carcinogenic in mice and rats. Gaus claims that, in this study, 4800 statistical comparisons were possible, and that 209 of them were statistically significant (p<0.05) compared with 240 (4800 × 0.05) expected by chance alone; thus, the carcinogenicity of Ginkgo biloba extract cannot be definitively established. However, his assumptions and calculations are flawed since he incorrectly assumes that the NTP uses no correction for multiple comparisons, and that significance tests for discrete data operate at exactly the nominal level. He also misrepresents the NTP’s decision making process, overstates the number of statistical comparisons made, and ignores that fact that that the mouse liver tumor effects were so striking (e.g., p<0.0000000000001) that it is virtually impossible that they could be false positive outcomes. Gaus’ conclusion that such obvious responses merely “generate a hypothesis” rather than demonstrate a real carcinogenic effect has no scientific credibility. Moreover, his claims regarding the high frequency of false positive outcomes in carcinogenicity studies are misleading because of his methodological misconceptions and errors. PMID:25261588

  14. Artificial Intelligence and Machine Learning in Radiology: Opportunities, Challenges, Pitfalls, and Criteria for Success.

    PubMed

    Thrall, James H; Li, Xiang; Li, Quanzheng; Cruz, Cinthia; Do, Synho; Dreyer, Keith; Brink, James

    2018-03-01

    Worldwide interest in artificial intelligence (AI) applications, including imaging, is high and growing rapidly, fueled by availability of large datasets ("big data"), substantial advances in computing power, and new deep-learning algorithms. Apart from developing new AI methods per se, there are many opportunities and challenges for the imaging community, including the development of a common nomenclature, better ways to share image data, and standards for validating AI program use across different imaging platforms and patient populations. AI surveillance programs may help radiologists prioritize work lists by identifying suspicious or positive cases for early review. AI programs can be used to extract "radiomic" information from images not discernible by visual inspection, potentially increasing the diagnostic and prognostic value derived from image datasets. Predictions have been made that suggest AI will put radiologists out of business. This issue has been overstated, and it is much more likely that radiologists will beneficially incorporate AI methods into their practices. Current limitations in availability of technical expertise and even computing power will be resolved over time and can also be addressed by remote access solutions. Success for AI in imaging will be measured by value created: increased diagnostic certainty, faster turnaround, better outcomes for patients, and better quality of work life for radiologists. AI offers a new and promising set of methods for analyzing image data. Radiologists will explore these new pathways and are likely to play a leading role in medical applications of AI. Copyright © 2017 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  15. Significance of stress transfer in time-dependent earthquake probability calculations

    USGS Publications Warehouse

    Parsons, T.

    2005-01-01

    A sudden change in stress is seen to modify earthquake rates, but should it also revise earthquake probability? Data used to derive input parameters permits an array of forecasts; so how large a static stress change is require to cause a statistically significant earthquake probability change? To answer that question, effects of parameter and philosophical choices are examined through all phases of sample calculations, Drawing at random from distributions of recurrence-aperiodicity pairs identifies many that recreate long paleoseismic and historic earthquake catalogs. Probability density funtions built from the recurrence-aperiodicity pairs give the range of possible earthquake forecasts under a point process renewal model. Consequences of choices made in stress transfer calculations, such as different slip models, fault rake, dip, and friction are, tracked. For interactions among large faults, calculated peak stress changes may be localized, with most of the receiving fault area changed less than the mean. Thus, to avoid overstating probability change on segments, stress change values should be drawn from a distribution reflecting the spatial pattern rather than using the segment mean. Disparity resulting from interaction probability methodology is also examined. For a fault with a well-understood earthquake history, a minimum stress change to stressing rate ratio of 10:1 to 20:1 is required to significantly skew probabilities with >80-85% confidence. That ratio must be closer to 50:1 to exceed 90-95% confidence levels. Thus revision to earthquake probability is achievable when a perturbing event is very close to the fault in question or the tectonic stressing rate is low.

  16. Do physicians clean their hands? Insights from a covert observational study.

    PubMed

    Kovacs-Litman, Adam; Wong, Kimberly; Shojania, Kaveh G; Callery, Sandra; Vearncombe, Mary; Leis, Jerome A

    2016-12-01

    Physicians are notorious for poor hand hygiene (HH) compliance. We wondered if lower performance by physicians compared with other health professionals might reflect differences in the Hawthorne effect. We introduced covert HH observers to see if performance differences between physicians and nurses decreased and to gain further insights into physician HH behaviors. Following training and validation with a hospital HH auditor, 2 students covertly measured HH during clinical rotations. Students rotated off clinical services every week to increase exposure to different providers and minimize risk of exposing the covert observation. We compared covertly measured HH compliance with data from overt observation by hospital auditors during the same time period. Covert observation produced much lower HH compliance than recorded by hospital auditors during the same time period: 50.0% (799/1597) versus 83.7% (2769/3309) (P < 0.0002). The difference in physician compliance between hospital auditors and covert observers was 19.0% (73.2% vs 54.2%); for nurses this difference was much higher at 40.7% (85.8% vs 45.1%) (P < 0.0001). Physician trainees showed markedly better compliance when attending staff cleaned their hands compared with encounters when attending did not (79.5% vs 18.9%; P < 0.0002). Our study suggests that traditional HH audits not only overstate HH performance overall, but can lead to inaccurate inferences about performance by professional groupings due to relative differences in the Hawthorne effect. We suggest that future improvement efforts will rely on more accurate HH monitoring systems and strong attending physician leadership to set an example for trainees. Journal of Hospital Medicine 2015;11:862-864. © 2015 Society of Hospital Medicine. © 2016 Society of Hospital Medicine.

  17. MOE vs. M&E: considering the difference between measuring strategic effectiveness and monitoring tactical evaluation.

    PubMed

    Diehl, Glen; Major, Solomon

    2015-01-01

    Measuring the effectiveness of military Global Health Engagements (GHEs) has become an area of increasing interest to the military medical field. As a result, there have been efforts to more logically and rigorously evaluate GHE projects and programs; many of these have been based on the Logic and Results Frameworks. However, while these Frameworks are apt and appropriate planning tools, they are not ideally suited to measuring programs' effectiveness. This article introduces military medicine professionals to the Measures of Effectiveness for Defense Engagement and Learning (MODEL) program, which implements a new method of assessment, one that seeks to rigorously use Measures of Effectiveness (vs. Measures of Performance) to gauge programs' and projects' success and fidelity to Theater Campaign goals. While the MODEL method draws on the Logic and Results Frameworks where appropriate, it goes beyond their planning focus by using the latest social scientific and econometric evaluation methodologies to link on-the-ground GHE "lines of effort" to the realization of national and strategic goals and end-states. It is hoped these methods will find use beyond the MODEL project itself, and will catalyze a new body of rigorous, empirically based work, which measures the effectiveness of a broad spectrum of GHE and security cooperation activities. We based our strategies on the principle that it is much more cost-effective to prevent conflicts than it is to stop one once it's started. I cannot overstate the importance of our theater security cooperation programs as the centerpiece to securing our Homeland from the irregular and catastrophic threats of the 21st Century.-GEN James L. Jones, USMC (Ret.). Reprint & Copyright © 2015 Association of Military Surgeons of the U.S.

  18. Dissemination of 2014 dual antiplatelet therapy (DAPT) trial results: a systematic review of scholarly and media attention over 7 months.

    PubMed

    Sharp, Melissa K; Haneef, Romana; Ravaud, Philippe; Boutron, Isabelle

    2017-11-03

    To explore how the results from the 2014 dual antiplatelet therapy (DAPT) trial were disseminated to the scientific community and online media. A a systematic review of scholarly and public attention surrounding the DAPT study. Data were collected from the ISI Web of Knowledge, Google Scholar, PubMed Commons, EurekAlert, the DAPT study website (www.daptstudy.org) and the New England Journal of Medicine website (for scholarly attention) and Altmetric Explorer, Snap Bird, YouTube (for public attention) citing DAPT study results appearing from 16 November 2014 to 10 June 2015. No participants were involved in this study. Proportion of contents highlighting the increased risk of mortality and critical to the author's interpretation of the results. We identified 425 items reported by seven sources; 164 (39%) disseminated the authors' interpretation via an electronic link or a reference, with no additional text. Among 81 items (19 %), the message favoured prolonged treatment and consequently overstated the article conclusions. Among 119 items (28 %), the text was uncertain about the benefit of prolonged treatment but was reported with no or inappropriate mention of increased risk of mortality. Only 34 items (8 %) were uncertain about the benefit of prolonged treatment and mentioned increased risk of mortality. In all, 27 items (6 %) did not favour prolonged treatment, and only 12 of these (3 %) clearly raised some concerns about the reporting of increased risk of death. Dissemination of the DAPT study results to the scientific community and on different media sources rarely criticised the interpretation of the study results. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  19. Excess Length of Stay Attributable to Clostridium difficile Infection (CDI) in the Acute Care Setting: A Multistate Model.

    PubMed

    Stevens, Vanessa W; Khader, Karim; Nelson, Richard E; Jones, Makoto; Rubin, Michael A; Brown, Kevin A; Evans, Martin E; Greene, Tom; Slade, Eric; Samore, Matthew H

    2015-09-01

    Standard estimates of the impact of Clostridium difficile infections (CDI) on inpatient lengths of stay (LOS) may overstate inpatient care costs attributable to CDI. In this study, we used multistate modeling (MSM) of CDI timing to reduce bias in estimates of excess LOS. A retrospective cohort study of all hospitalizations at any of 120 acute care facilities within the US Department of Veterans Affairs (VA) between 2005 and 2012 was conducted. We estimated the excess LOS attributable to CDI using an MSM to address time-dependent bias. Bootstrapping was used to generate 95% confidence intervals (CI). These estimates were compared to unadjusted differences in mean LOS for hospitalizations with and without CDI. During the study period, there were 3.96 million hospitalizations and 43,540 CDIs. A comparison of unadjusted means suggested an excess LOS of 14.0 days (19.4 vs 5.4 days). In contrast, the MSM estimated an attributable LOS of only 2.27 days (95% CI, 2.14-2.40). The excess LOS for mild-to-moderate CDI was 0.75 days (95% CI, 0.59-0.89), and for severe CDI, it was 4.11 days (95% CI, 3.90-4.32). Substantial variation across the Veteran Integrated Services Networks (VISN) was observed. CDI significantly contributes to LOS, but the magnitude of its estimated impact is smaller when methods are used that account for the time-varying nature of infection. The greatest impact on LOS occurred among patients with severe CDI. Significant geographic variability was observed. MSM is a useful tool for obtaining more accurate estimates of the inpatient care costs of CDI.

  20. Power Policy 21 Century: Growth of the Population, Economics, Ecology and Entropy

    NASA Astrophysics Data System (ADS)

    Prisniakov, Vladimir

    2002-01-01

    but energy consumed by a man will be a limiting factor. Obtained values of changing in the quantity of population as well as of the consumed fuel quantity in the 21 century have been analysed. The period was defined (2005-2085) when energy hungry is possible due to a higher rate of a human reproduction comparing to the rates of energy consumption. From new position, the laws of the Earth population growth are analysed, based on the equality of the quantity of dying people to the quantity of those bornyears ago, whereis life expectancy. investigated on the base of Second law of thermodynamics. The equation of money exchange dY = (V/p)dM in going from quantity real GNP Y to consumption fuel equivalent E=pd Y takes the form: dE =VdM. General correlation between S and M is proposed: dS = (HV/T)dM, where H is enthalpy; V is velocity of money; T is temperature; p is total prices,is capacity of manufacture resources. This equation shows direction of the spontaneity development of economical processes as part of general law Universe. The original equation of removing from information to matter equation enables to control output natural resources by economic laws, and to control of activities for the restoration wrecked nature.This equation shows the direction of the spontaneity development of economical processes as part of a general Universal law. into account value of expenditure on ecology as part of price and overstated price indexes. The criterions allow to discover numerical values of a stock of money, ecology part of price, velocity of money, value of the taxes, which ensure sustainable development. These equations enable to control output natural resources by economic laws, and to control activities for the restoration of wrecked nature.

  1. Pulmonary embolism at autopsy in a normal population: implications for air travel fatalities.

    PubMed

    Pheby, D F H; Codling, B W

    2002-12-01

    Much attention has been focused on the apparent risk to long-haul air travelers of venous thromboembolism [deep vein thrombosis (DVT) and pulmonary embolism (PE)], following a number of well-publicized cases. However, there is little epidemiological data to elucidate the problem. PE tends to be under-diagnosed as a cause of death in the general population. This study sets out to establish the level of risk of fatal PE among long-haul passengers arriving in the UK, on the basis of a reappraisal of the role of PE in mortality in the general population. Autopsies carried out at Gloucester in 1996-2000 were reviewed to determine age-specific mortality rates for PE for West Gloucestershire. These rates were applied to long-haul air travelers arriving in the UK, for whom the number of passenger-years at risk were calculated, to estimate the expected numbers of deaths in this group. In 3764 autopsies, PE was the primary cause of death in 221 cases (5.9%), while in 304 (8.1%) it was present as an incidental finding. This suggests that PE was involved in approximately 13.9% of deaths, and is more common with age. Passenger years at risk per annum among long-haul passengers arriving in the UK were estimated (mid-range) at 21,830.482; it was anticipated that 6.55 deaths involving PEs, but not related to air travel, could be expected annually in this group. It appears that the risks of venous thromboembolism due to air travel are overstated. Some deaths are bound to occur inflight, but there is no evidence to suggest an increase, though clearly there are predisposing risk factors for DVT present on long journeys.

  2. Complication Rates of 3% Hypertonic Saline Infusion Through Peripheral Intravenous Access.

    PubMed

    Perez, Claudia Andira; Figueroa, Stephen A

    2017-06-01

    Hyperosmolar therapy with hypertonic saline (HTS) is a cornerstone in the management of intracranial hypertension and hyponatremia in the neurological intensive care unit. Theoretical safety concerns remain for infiltration, thrombophlebitis, tissue ischemia, and venous thrombosis associated with continuous 3% HTS administered via peripheral intravenous (pIV) catheters. It is common practice at many institutions to allow only central venous catheter infusion of 3% HTS. Hospital policy was changed to allow the administration of 3% HTS via 16- to 20-gauge pIVs to a maximum infusion rate of 50 mL/h in patients without central venous access. We prospectively monitored patients who received peripheral 3% HTS as part of a quality improvement project. We documented gauge, location, maximum infusion rate, and total hours of administration. Patients were assessed for infiltration, erythema, swelling, phlebitis, thrombosis, and line infection. There were 28 subjects across 34 peripheral lines monitored. Overall, subjects received 3% HTS for a duration between 1 and 124 hours with infusion rates of 30 to 50 mL/h. The rate of complications observed was 10.7% among all subjects. Documented complications included infiltration (n = 2), with an incidence of 6%, and thrombophlebitis (n = 1), with an incidence of 3%. There has been a long concern among healthcare providers, including nursing staff, in regard to pIV administration of prolonged 3% HTS infusion therapy. Our study indicates that peripheral administration of 3% HTS carries a low risk of minor, nonlimb, or life-threatening complications. Although central venous infusion may reduce the risk of these minor complications, it may increase the risk of more serious complications such as large vessel thrombosis, bloodstream infection, pneumothorax, and arterial injury. The concern regarding the risks of pIV administration of 3% HTS may be overstated and unfounded.

  3. Prevention in practice – a summary.

    PubMed Central

    2015-01-01

    Background This paper is a summary document of the Prevention in Practice Conference and Special Supplement of BMC Oral Health. It represents the consensus view of the presenters and captures the questions, comments and suggestions of the assembled audience. Methods Using the prepared manuscripts for the conference, collected materials from scribes during the conference and additional resources collated in advance of the meeting, authors agreed on the summary document. Results The Prevention in Practice conference aimed to collate information about which diseases could be prevented in practice, how diseases could be identified early enough to facilitate prevention, what evidence based therapies and treatments were available and how, given the collective evidence, could these be introduced in general dental practice within different reimbursement models. Conclusions While examples of best practice were provided from both social care and insurance models it was clear that further work was required on both provider and payer side to ensure that evidence based prevention was both implemented properly but also reimbursed sufficiently. It is clear that savings can be made but these must not be overstated and that the use of effective skill mix would be key to realizing efficiencies. The evidence base for prevention of caries and periodontal disease has been available for many years, as have the tools and techniques to detect, diagnose and stage the diseases appropriately. Dentistry finds itself in a enviable position with respect to its ability to prevent, arrest and reverse much of the burden of disease, however, it is clear that the infrastructure within primary care must be changed, and practitioners and their teams appropriately supported to deliver this paradigm shift from a surgical to a medical model. PMID:26391906

  4. How ideology shapes the evidence and the policy: what do we know about cannabis use and what should we do?

    PubMed

    Macleod, John; Hickman, Matthew

    2010-08-01

    In the United Kingdom, as in many places, cannabis use is considered substantially within a criminal justice rather than a public health paradigm with prevention policy embodied in the Misuse of Drugs Act. In 2002 the maximum custodial sentence tariff for cannabis possession under the Act was reduced from 5 to 2 years. Vigorous and vociferous public debate followed this decision, centred principally on the question of whether cannabis use caused schizophrenia. It was suggested that new and compelling evidence supporting this hypothesis had emerged since the re-classification decision was made, meaning that the decision should be reconsidered. The re-classification decision was reversed in 2008. We consider whether the strength of evidence on the psychological harms of cannabis has changed substantially and discuss the factors that may have influenced recent public discourse and policy decisions. We also consider evidence for other harms of cannabis use and public health implications of preventing cannabis use. We conclude that the strongest evidence of a possible causal relation between cannabis use and schizophrenia emerged more than 20 years ago and that the strength of more recent evidence may have been overstated--for a number of possible reasons. We also conclude that cannabis use is almost certainly harmful, mainly because of its intimate relation to tobacco use. The most rational policy on cannabis from a public health perspective would seem to be one able to achieve the benefit of reduced use in the population while minimizing social and other costs of the policy itself. Prohibition, whatever the sentence tariff associated with it, seems unlikely to fulfil these criteria.

  5. New Insights into the Explosion Source from SPE

    NASA Astrophysics Data System (ADS)

    Patton, H. J.

    2015-12-01

    Phase I of the Source Physics Experiments (SPE) is a series of chemical explosions at varying depths and yields detonated in the same emplacement hole on Climax stock, a granitic pluton located on the Nevada National Security Site. To date, four of the seven planned tests have been conducted, the last in May 2015, called SPE-4P, with a scaled depth of burial of 1549 m/kt1/3 in order to localize the source in time and space. Surface ground motions validated that the source medium did not undergo spallation, and a key experimental objective was achieved where SPE-4P is the closest of all tests in the series to a pure monopole source and will serve as an empirical Green's function for analysis against other SPE tests. A scientific objective of SPE is to understand mechanisms of rock damage for generating seismic waves, particularly surface and S waves, including prompt damage under compressive stresses and "late-time" damage under tensile stresses. Studies have shown that prompt damage can explain ~75% of the seismic moment for some SPE tests. Spallation is a form of late-time damage and a facilitator of damage mechanisms under tensile stresses including inelastic brittle deformation and shear dilatancy on pre-existing faults or joints. As an empirical Green's function, SPE-4P allows the study of late-time damage mechanisms on other SPE tests that induce spallation and late-time damage, and I'll discuss these studies. The importance for nuclear monitoring cannot be overstated because new research shows that damage mechanisms can affect surface wave magnitude Ms more than tectonic release, and are a likely factor related to anomalous mb-Ms behavior for North Korean tests.

  6. An isoline separating relatively warm from relatively cool wintertime forest surface temperatures for the southeastern United States

    NASA Astrophysics Data System (ADS)

    Wickham, J.; Wade, T. G.; Riitters, K. H.

    2014-09-01

    Forest-oriented climate mitigation policies promote forestation as a means to increase uptake of atmospheric carbon to counteract global warming. Some have pointed out that a carbon-centric forest policy may be overstated because it discounts biophysical aspects of the influence of forests on climate. In extra-tropical regions, many climate models have shown that forests tend to be warmer than grasslands and croplands because forest albedos tend to be lower than non-forest albedos. A lower forest albedo results in higher absorption of solar radiation and increased sensible warming that is not offset by the cooling effects of carbon uptake in extra-tropical regions. However, comparison of forest warming potential in the context of climate models is based on a coarse classification system of tropical, temperate, and boreal. There is considerable variation in climate within the broad latitudinal zonation of tropical, temperate, and boreal, and the relationship between biophysical (albedo) and biogeochemical (carbon uptake) mechanisms may not be constant within these broad zones. We compared wintertime forest and non-forest surface temperatures for the southeastern United States and found that forest surface temperatures shifted from being warmer than non-forest surface temperatures north of approximately 36°N to cooler south of 36°N. Our results suggest that the biophysical aspects of forests' influence on climate reinforce the biogeochemical aspects of forests' influence on climate south of 36°N. South of 36°N, both biophysical and biogeochemical properties of forests appear to support forestation as a climate mitigation policy. We also provide some quantitative evidence that evergreen forests tend to have cooler wintertime surface temperatures than deciduous forests that may be attributable to greater evapotranspiration rates.

  7. Hot Idea or Hot Air: A Systematic Review of Evidence for Two Widely Marketed Youth Suicide Prevention Programs and Recommendations for Implementation

    PubMed Central

    Wei, Yifeng; Kutcher, Stan; LeBlanc, John C.

    2015-01-01

    Introduction: Youth suicide is highly related to mental disorders. While communities and schools are marketed to with a plethora of suicide prevention programs, they often lack the capacity to choose evidence-based programs. Methods: We conducted a systematic review of two youth suicide prevention programs to help determine if the quality of evidence available justifies their wide spread dissemination. We searched Medline, PsycINFO, EMBASE, CINAHL, the Cochrane Library, Campbell Collaboration SPECTR database, SocIndex, Sociological Abstracts, Social Services Abstracts, ERIC, Social Work Abstracts, Research Library, and Web of Science, for relevant studies. We included studies/systematic reviews/meta-analysis that evaluated the effectiveness, cost-effectiveness, and/or safety of Signs of Suicide (SOS) and Yellow Ribbon (YR) suicide prevention programs that target adolescents. We applied the Office of Justice Program What Works Repository (OJP-R) to evaluate the quality of the included studies as effective, effective with reservation, promising, inconclusive evidence, insufficient evidence, and ineffective. Two SOS studies were ranked as “inconclusive evidence” based on the OJP-R. One SOS study was ranked as having “insufficient evidence” on OJP-R. The YR study was ranked as “ineffective” using OJP-R. We only included studies in peer-reviewed journals in English and therefore may have missed reports in grey literature or non-English publications. Results: We cannot recommend that schools and communities implement either the SOS or YR suicide prevention programs. Purchasers of these programs should be aware that there is no evidence that their use prevents suicide. Conclusions: Academics and organizations should not overstate the positive impacts of suicide prevention interventions when the evidence is lacking. PMID:26336375

  8. Robotic cystectomy and the Internet: separating fact from fiction.

    PubMed

    Pruthi, Raj S; Belsante, Jim; Kurpad, Raj; Nielsen, Matthew E; Wallen, Eric M

    2011-01-01

    Patients commonly use the Internet to acquire health information. While a large amount of health-related information is available, the accuracy is highly variable. We sought to evaluate the current web-based information that exists with regard to robotic cystectomy. Two common search engines (Google and Yahoo) were used to search the term "robotic cystectomy" and obtain the top 50 websites for each. These 100 sites were analyzed with regard to type of site, presence and accuracy of information on bladder cancer, and of information related to robotic cystectomy outcomes (surgical/oncologic, functional, and recovery). In addition, information taken from Intuitive Corp website was identified, as was the presence (or absence) and literature-based references. Of the 100 sites, 61 were surgeon/provider sites, 23 links to articles, 8 news stories, 3 patient support sites, 3 meeting program, and 2 were the Intuitive site. Analysis of all 61 provider sites showed that 13% provided factually accurate information, 7% had both factual and erroneous information, and 80% had no information on bladder cancer. With regard to the purported benefits and outcomes of the robotic approach, a significant number of the sites had nonevidence-based claims with regard surgical/oncologic aspects (54%), functional recovery (26%), and surgical recovery (47%). Information taken directly from the Intuitive site was found on 33% sites, with 16% sites having a direct link. Only 4 provider sites (7%) had listed any references. These findings suggest that surgeons provide the majority of Internet information but do not often present evidence-based information and often over-state claims and outcomes of the robotic approach. This highlights the need for providers to deliver factual and evidence-based information to the public, and not suggest untrue/unproven claims that seem to presently occur. Copyright © 2011 Elsevier Inc. All rights reserved.

  9. Environmental drivers of cambial phenology in Great Basin bristlecone pine.

    PubMed

    Ziaco, Emanuele; Biondi, Franco; Rossi, Sergio; Deslauriers, Annie

    2016-07-01

    The timing of wood formation is crucial to determine how environmental factors affect tree growth. The long-lived bristlecone pine (Pinus longaeva D. K. Bailey) is a foundation treeline species in the Great Basin of North America reaching stem ages of about 5000 years. We investigated stem cambial phenology and radial size variability to quantify the relative influence of environmental variables on bristlecone pine growth. Repeated cellular measurements and half-hourly dendrometer records were obtained during 2013 and 2014 for two high-elevation stands included in the Nevada Climate-ecohydrological Assessment Network. Daily time series of stem radial variations showed rehydration and expansion starting in late April-early May, prior to the onset of wood formation at breast height. Formation of new xylem started in June and lasted until mid-September. There were no differences in phenological timing between the two stands, or in the air and soil temperature thresholds for the onset of xylogenesis. A multiple logistic regression model highlighted a separate effect of air and soil temperature on xylogenesis, the relevance of which was modulated by the interaction with vapor pressure and soil water content. While air temperature plays a key role in cambial resumption after winter dormancy, soil thermal conditions coupled with snowpack dynamics also influence the onset of wood formation by regulating plant-soil water exchanges. Our results help build a physiological understanding of climate-growth relationships in P. longaeva, the importance of which for dendroclimatic reconstructions can hardly be overstated. In addition, environmental drivers of xylogenesis at the treeline ecotone, by controlling the growth of dominant species, ultimately determine ecosystem responses to climatic change. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Has the Time Come to Stratify and Score SUDEP Risk to Inform People With Epilepsy of Their Changes in Safety?

    PubMed Central

    Shankar, Rohit; Newman, Craig; Gales, Alistair; McLean, Brendan N.; Hanna, Jane; Ashby, Samantha; Walker, Matthew C.; Sander, Josemir W.

    2018-01-01

    Recent publication of the American Academy of Neurology SUDEP guidance highlighted the importance to American clinicians of making people with epilepsy aware of SUDEP risk. It is the first guideline to do this in the United States. It follows precedent set out in the UK by National Institute of Clinical Excellence in 2004. While a significant achievement, the lack of clarity of how to deliver this guidance in an enduring and person-centered manner, raises concerns on how its long-term effectiveness in risk mitigation. Shared decision-making with an emphasis on delivering person-centered communication to foster self-management strategies is increasingly recognized as the ideal model of patient–clinician communication in chronic diseases such as epilepsy. The tension between delivering evidence-based risk information, yet, tailoring it to the individual is complex. It needs to incorporate the potential for change not only in seizure factors but also other health and social factors. Safety advice needs to be dynamic and situation sensitive as opposed to a “one off” discussion. As a significant minority of people with epilepsy have drug-resistant seizures, the importance of keeping the advice contextual at different intervals of the person’s life cannot be overstated as many of them are managed in primary care. We present some exploratory work, which identifies the need to improve communication at a primary care level and to review risks regularly. Regular reviews using a structured risk factor checklist as a screening tool could identify, sooner, people who’s health issues are worsening and justify referrals to specialists. PMID:29755403

  11. Project planning, training, measurement and sustainment: the successful implementation of voice recognition.

    PubMed

    Antiles, S; Couris, J; Schweitzer, A; Rosenthal, D; Da Silva, R Q

    2000-01-01

    Computerized voice recognition systems (VR) can reduce costs and enhance service. The capital outlay required for conversion to a VR system is significant; therefore, it is incumbent on radiology departments to provide cost and service justifications to administrators. Massachusetts General Hospital (MGH) in Boston implemented VR over a two-year period and achieved annual savings of $530,000 and a 50% decrease in report throughput. Those accomplishments required solid planning and implementation strategies, training and sustainment programs. This article walks through the process, step by step, in the hope of providing a tool set for future implementations. Because VR has dramatic implications for workflow, a solid operational plan is needed when assessing vendors and planning for implementation. The goals for implementation should be to minimize operational disruptions and capitalize on efficiencies of the technology. Senior leadership--the department chair or vice-chair--must select the goals to be accomplished and oversee, manage and direct the VR initiative. The importance of this point cannot be overstated, since implementation will require behavior changes from radiologists and others who may not perceive any personal benefits. Training is the pivotal factor affecting the success of voice recognition, and practice is the only way for radiologists to enhance their skills. Through practice, radiologists will discover shortcuts, and their speed and comfort will improve. Measurement and data analysis are critical to changing and improving the voice recognition application and are vital to decision-making. Some of the issues about which valuable date can be collected are technical and educational problems, VR penetration, report turnaround time and annual cost savings. Sustained effort is indispensable to the maintenance of voice recognition. Finally, all efforts made and gains achieved may prove to be futile without ongoing sustainment of the system through retraining, education and technical support.

  12. Evaluation of aquaporin-4 antibody assays

    PubMed Central

    Waters, Patrick J.; Pittock, Sean J.; Bennett, Jeffrey L.; Jarius, Sven; Weinshenker, Brian G.; Wingerchuk, Dean M.

    2015-01-01

    Aquaporin-4 (AQP4) is a water channel protein that is most highly, but not exclusively, expressed in the central nervous system. In 2005 AQP4 was shown to be the antigenic target of neuromyelitis optica-immunoglobulin G (NMO-IgG, or AQP4-IgG), an antibody found specifically in patients with NMO and in formes frustes of NMO, such as longitudinally extensive transverse myelitis (LETM) or optic neuritis (ON). This discovery facilitated the clinical, pathological, and radiological distinction of NMO and the spectrum of NMO-related disorders from classical multiple sclerosis. In addition to its use as a diagnostic tool, AQP4-IgG predicts a high risk of relapse in patients with a clinically isolated syndrome of either LETM or ON. As disability in NMO is attack-related, early diagnosis and treatment are predicted to have a major effect on long-term disability. Thus, the importance of sensitive and specific assays to detect AQP4-IgG cannot be overstated. Both academic institutions and commercial companies have developed assays to identify AQP4-IgG in patients’ sera or cerebrospinal fluid. Both AQP4 isoforms from different species have been used as the antigenic target in the form of frozen tissue sections in indirect immunofluorescence assays, partially purified protein for fluorescence immunoprecipitation assay, radioimmunoprecipita-tion assay or enzyme-linked immunosorbent assay, or transfected into cells for cell based assays or flow cytometry. We carried out a systematic review of the literature reporting different methodologies used to identify AQP4-IgG, examine whether longitudinal AQP4-IgG titers predict relapses in seropositive patients, and attempt to establish a reasonable timeframe for retesting negative serum samples. PMID:27840658

  13. Expensing options solves nothing.

    PubMed

    Sahlman, William A

    2002-12-01

    The use of stock options for executive compensation has become a lightning rod for public anger, and it's easy to see why. Many top executives grew hugely rich on the back of the gains they made on their options, profits they've been able to keep even as the value they were supposed to create disappeared. The supposed scam works like this: Current accounting regulations let companies ignore the cost of option grants on their income statements, so they can award valuable option packages without affecting reported earnings. Not charging the cost of the grants supposedly leads to overstated earnings, which purportedly translate into unrealistically high share prices, permitting top executives to realize big gains when they exercise their options. If an accounting anomaly is the problem, then the solution seems obvious: Write off executive share options against the current year's revenues. The trouble is, Sahlman writes, expensing option grants won't give us a more accurate view of earnings, won't add any information not already included in the financial statements, and won't even lead to equal treatment of different forms of executive pay. Far worse, expensing evades the real issue, which is whether compensation (options and other-wise) does what it's supposed to do--namely, help a company recruit, retain, and provide the right people with appropriate performance incentives. Any performance-based compensation system has the potential to encourage cheating. Only ethical management, sensible governance, adequate internal control systems, and comprehensive disclosure will save the investor from disaster. If, Sahlman warns, we pass laws that require the expensing of options, thinking that's fixed the fundamental flaws in corporate America's accounting, we will have missed a golden opportunity to focus on the much more extensive defects in the present system.

  14. Can Hall effect trigger Kelvin-Helmholtz instability in sub-Alfvénic flows?

    NASA Astrophysics Data System (ADS)

    Pandey, B. P.

    2018-05-01

    In the Hall magnetohydrodynamics, the onset condition of the Kelvin-Helmholtz instability is solely determined by the Hall effect and is independent of the nature of shear flows. In addition, the physical mechanism behind the super- and sub-Alfvénic flows becoming unstable is quite different: the high-frequency right circularly polarized whistler becomes unstable in the super-Alfvénic flows whereas low-frequency, left circularly polarized ion-cyclotron wave becomes unstable in the presence of sub-Alfvénic shear flows. The growth rate of the Kelvin-Helmholtz instability in the super-Alfvénic case is higher than the corresponding ideal magnetohydrodynamic rate. In the sub-Alfvénic case, the Hall effect opens up a new, hitherto inaccessible (to the magnetohydrodynamics) channel through which the partially or fully ionized fluid can become Kelvin-Helmholtz unstable. The instability growth rate in this case is smaller than the super-Alfvénic case owing to the smaller free shear energy content of the flow. When the Hall term is somewhat smaller than the advection term in the induction equation, the Hall effect is also responsible for the appearance of a new overstable mode whose growth rate is smaller than the purely growing Kelvin-Helmholtz mode. On the other hand, when the Hall diffusion dominates the advection term, the growth rate of the instability depends only on the Alfvén -Mach number and is independent of the Hall diffusion coefficient. Further, the growth rate in this case linearly increases with the Alfvén frequency with smaller slope for sub-Alfvénic flows.

  15. The balance sheet technique. Volume I. The balance sheet analysis technique for preconstruction review of airports and highways

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    LaBelle, S.J.; Smith, A.E.; Seymour, D.A.

    1977-02-01

    The technique applies equally well to new or existing airports. The importance of accurate accounting of emissions, cannot be overstated. The regional oxidant modelling technique used in conjunction with a balance sheet review must be a proportional reduction technique. This type of emission balancing presumes equality of all sources in the analysis region. The technique can be applied successfully in the highway context, either in planning at the system level or looking only at projects individually. The project-by-project reviews could be used to examine each project in the same way as the airport projects are examined for their impact onmore » regional desired emission levels. The primary limitation of this technique is that it should not be used when simulation models have been used for regional oxidant air quality. In the case of highway projects, the balance sheet technique might appear to be limited; the real limitations are in the transportation planning process. That planning process is not well-suited to the needs of air quality forecasting. If the transportation forecasting techniques are insensitive to change in the variables that affect HC emissions, then no internal emission trade-offs can be identified, and the initial highway emission forecasts are themselves suspect. In general, the balance sheet technique is limited by the quality of the data used in the review. Additionally, the technique does not point out effective trade-off strategies, nor does it indicate when it might be worthwhile to ignore small amounts of excess emissions. Used in the context of regional air quality plans based on proportional reduction models, the balance sheet analysis technique shows promise as a useful method by state or regional reviewing agencies.« less

  16. Is leadership and management in inter-agency settings really that different? Perspectives from the literature

    PubMed Central

    Dickinson, Helen; Peck, Edward

    2008-01-01

    Introduction Health and social care collaboration is currently a key feature of improvement efforts internationally. Moreover, leadership is increasingly considered an important driver in terms of organisational performance, in particular in relation to the implementation of policy designed to solve the wicked issues of society. Yet, despite leadership being viewed as an essential component of integrative public sector performance, there is relatively little thoughtful work analysing the relationship between the two sets of ideas. Leadership in collaborative settings is simultaneously represented as being both the same, and yet different, to these roles in more traditional settings. What this means in practice is that much of the literature appears somewhat at best platitudinous and at worst confused—posing practical difficulties for leaders and managers of collaborations who are looking for evidence or guidance on how to enact leadership. Aims and objectives This paper examines the literature and asks how different leadership in inter-agency settings is from more ‘traditional’ settings, before going on to map out lessons which may be useful for leaders and managers to draw upon in more effectively navigating this difficult terrain. Methods This research is based on an extensive review of the literature surrounding leadership, collaboration and broader theories of networks. Results The paper finds that this distinction is overstated; there are also significant overlaps in the types of tasks and challenges that both sets of leaders and managers will face and these should not be underestimated. Conclusions This has clear implications for training and development of these individuals where understanding of the contexts for and nature of partnerships—and thus the sensemaking and performance that may be most effective—may be as important as the skills and attributes themselves.

  17. Nasolacrimal duct obstruction: Does it really increase the risk of amblyopia in children?

    PubMed

    Ramkumar, V Akila; Agarkar, Sumita; Mukherjee, Bipasha

    2016-07-01

    To report the prevalence of amblyopia risk factors in children with congenital nasolacrimal duct obstruction. A retrospective review of records of children with the diagnosis of congenital nasolacrimal duct obstruction (NLDO), who underwent probing from January 2009 to October 2011, was done. All of them underwent a complete ophthalmic evaluation including cycloplegic refraction and strabismus evaluation before probing. A total of 142 children were included in this study. The mean age at presentation was 22.38 months (sample standard deviation (SSD) - 15.88). Amblyopia risk factors were defined according to two sets of guidelines: The American Association for Pediatric Ophthalmology and Strabismus (AAPOS) referral criteria guidelines and the new AAPOS Vision Screening Committee guidelines. Twenty-eight (20%) children were found to have some form of amblyopia risk factor based on the referral criteria prescribed by AAPOS. However, on applying modified guidelines described by Donahue et al., to analyze the same cohort, 21 children were found to have amblyogenic risk factors. Of these 28 children, 13 had significant astigmatism (>1.50 D), 8 children had hypermetropia (>3.50 D), and six children had anisometropia (>1.50 D). One child had significant cataract (media opacity >1 mm). None of the children in this series had either myopia or strabismus. Prevalence of amblyopia risk factor was found to be 20% in our study based on the older guidelines; however, it reduces to 14.78% by applying the modified guidelines. Despite this reduction, importance of a comprehensive ophthalmic examination including cycloplegic refraction in all children presenting with NLDO cannot be overstated. A close follow-up of these children is also essential to prevent the development of amblyopia.

  18. Deconstructing tolerance with clobazam: Post hoc analyses from an open-label extension study.

    PubMed

    Gidal, Barry E; Wechsler, Robert T; Sankar, Raman; Montouris, Georgia D; White, H Steve; Cloyd, James C; Kane, Mary Clare; Peng, Guangbin; Tworek, David M; Shen, Vivienne; Isojarvi, Jouko

    2016-10-25

    To evaluate potential development of tolerance to adjunctive clobazam in patients with Lennox-Gastaut syndrome. Eligible patients enrolled in open-label extension study OV-1004, which continued until clobazam was commercially available in the United States or for a maximum of 2 years outside the United States. Enrolled patients started at 0.5 mg·kg -1 ·d -1 clobazam, not to exceed 40 mg/d. After 48 hours, dosages could be adjusted up to 2.0 mg·kg -1 ·d -1 (maximum 80 mg/d) on the basis of efficacy and tolerability. Post hoc analyses evaluated mean dosages and drop-seizure rates for the first 2 years of the open-label extension based on responder categories and baseline seizure quartiles in OV-1012. Individual patient listings were reviewed for dosage increases ≥40% and increasing seizure rates. Data from 200 patients were included. For patients free of drop seizures, there was no notable change in dosage over 24 months. For responder groups still exhibiting drop seizures, dosages were increased. Weekly drop-seizure rates for 100% and ≥75% responders demonstrated a consistent response over time. Few patients had a dosage increase ≥40% associated with an increase in seizure rates. Two-year findings suggest that the majority of patients do not develop tolerance to the antiseizure actions of clobazam. Observed dosage increases may reflect best efforts to achieve seizure freedom. It is possible that the clinical development of tolerance to clobazam has been overstated. NCT00518713 and NCT01160770. This study provides Class III evidence that the majority of patients do not develop tolerance to clobazam over 2 years of treatment. © 2016 American Academy of Neurology.

  19. Deconstructing tolerance with clobazam

    PubMed Central

    Wechsler, Robert T.; Sankar, Raman; Montouris, Georgia D.; White, H. Steve; Cloyd, James C.; Kane, Mary Clare; Peng, Guangbin; Tworek, David M.; Shen, Vivienne; Isojarvi, Jouko

    2016-01-01

    Objective: To evaluate potential development of tolerance to adjunctive clobazam in patients with Lennox-Gastaut syndrome. Methods: Eligible patients enrolled in open-label extension study OV-1004, which continued until clobazam was commercially available in the United States or for a maximum of 2 years outside the United States. Enrolled patients started at 0.5 mg·kg−1·d−1 clobazam, not to exceed 40 mg/d. After 48 hours, dosages could be adjusted up to 2.0 mg·kg−1·d−1 (maximum 80 mg/d) on the basis of efficacy and tolerability. Post hoc analyses evaluated mean dosages and drop-seizure rates for the first 2 years of the open-label extension based on responder categories and baseline seizure quartiles in OV-1012. Individual patient listings were reviewed for dosage increases ≥40% and increasing seizure rates. Results: Data from 200 patients were included. For patients free of drop seizures, there was no notable change in dosage over 24 months. For responder groups still exhibiting drop seizures, dosages were increased. Weekly drop-seizure rates for 100% and ≥75% responders demonstrated a consistent response over time. Few patients had a dosage increase ≥40% associated with an increase in seizure rates. Conclusions: Two-year findings suggest that the majority of patients do not develop tolerance to the antiseizure actions of clobazam. Observed dosage increases may reflect best efforts to achieve seizure freedom. It is possible that the clinical development of tolerance to clobazam has been overstated. ClinicalTrials.gov identifier: NCT00518713 and NCT01160770. Classification of evidence: This study provides Class III evidence that the majority of patients do not develop tolerance to clobazam over 2 years of treatment. PMID:27683846

  20. Breast Imaging-Reporting and Data System (BI-RADS) classification in 51 excised palpable pediatric breast masses.

    PubMed

    Koning, Jeffrey L; Davenport, Katherine P; Poole, Patricia S; Kruk, Peter G; Grabowski, Julia E

    2015-10-01

    The American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) classification was developed to risk stratify breast lesions and guide surgical management based on imaging. Previous studies validating BI-RADS for US do not include pediatric patients. Most pediatric breast masses present as palpable lesions and frequently undergo ultrasound, which is often accompanied with a BI-RADS classification. Our study aimed to correlate BI-RADS with pathology findings to assess applicability of the classification system to pediatric patients. We performed a retrospective review of all patients who underwent excision of a breast mass at a single center from July 2010 to November 2013. We identified all patients who underwent preoperative ultrasound with BI-RADS classification. Demographic data, imaging results, and surgical pathology were analyzed and correlated. A total of 119 palpable masses were excised from 105 pediatric patients during the study period. Of 119 masses, 81 had preoperative ultrasound, and BI-RADS categories were given to 51 masses. Of these 51, all patients were female and the average age was 15.9 years. BI-RADS 4 was given to 25 of 51 masses (49%), and 100% of these lesions had benign pathology, the most common being fibroadenoma. Treatment algorithm based on BI-RADS classification may not be valid in pediatric patients. In this study, all patients with a BI-RADS 4 lesion had benign pathology. BI-RADS classification may overstate the risk of malignancy or need for biopsy in this population. Further validation of BI-RADS classification with large scale studies is needed in pediatric and adolescent patients. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Effect of Different Angular Momentum Transport Mechanisms on the Radial Volatile Distribution in Protoplanetary Disks

    NASA Astrophysics Data System (ADS)

    Kalyaan, Anusha; Desch, Steven

    2018-01-01

    How circumstellar disks evolve and transport angular momentum is a mystery even until today. Magnetorotational instability (MRI; [1]) earlier thought to be a primary driver of disk evolution, has been found to be not as strong a candidate in cold insufficiently ionized protoplanetary disks where non-ideal MHD effects take over to efficiently suppress the instability [2][3]. In the past few years, recent studies have proposed different mechanisms such as magnetically-driven disk winds [4][5], convective overstability [6], and the vertical shear instability (VSI)[7] to be likely drivers of disk evolution. In this work, we consider numerically [8] and/or parametrically derived radial α profiles of three different mechanisms of angular momentum transport (hydrodynamic instabilities such as VSI, disk winds, and MRI) to understand how the underlying disk structure changes and evolves with each mechanism. We overlay our snowline model that incorporates the advection and diffusion of volatiles as well as radial drift of solids [9] to understand how different α profiles can affect the distribution of water in the disk. References: [1] Balbus, S.A., & Hawley, J.F.,1998, Rev. of Mod. Phys., 70, 1 [2] Bai, X.-N., & Stone, J.M. 2011, ApJ, 736, 144 [3] Bai, X.-N., & Stone, J.M., 2013, ApJ, 769, 76 [4] Bai, X.-N., 2016, ApJ, 821, 80 [5] Suzuki, T.K., Ogihara, M., Morbidelli, A., Crida, A., & Guillot, T., 2016, A&A, 596, A74 [6] Klahr, H., & Hubbard, A. 2014, ApJ, 788, 21 [7] Stoll, M.H.R., & Kley, W. 2014, A&A, 572, A77 [8] Kalyaan, A., Desch, S.J., & Monga, N., 2015, ApJ, 815, 112 [9] Desch, S.J., Estrada, P.R., Kalyaan, A., & Cuzzi, J.N., 2017, ApJ, 840, 86

  2. Influence of acute exercise with and without carbohydrate replacement on postprandial lipid metabolism.

    PubMed

    Harrison, Michael; O'Gorman, Donal J; McCaffrey, Noel; Hamilton, Marc T; Zderic, Theodore W; Carson, Brian P; Moyna, Niall M

    2009-03-01

    Acute exercise, undertaken on the day before an oral fat tolerance test (OFTT), typically reduces postprandial triglycerides (TG) and increases high-density lipoprotein-cholesterol (HDL-C). However, the benefits of acute exercise may be overstated when studies do not account for compensatory changes in dietary intake. The objective of this study was to determine the influence of acute exercise, with and without carbohydrate (CHO) replacement, on postprandial lipid metabolism. Eight recreationally active young men underwent an OFTT on the morning after three experimental conditions: no exercise [control (Con)], prolonged exercise without CHO replacement (Ex-Def) and prolonged exercise with CHO replacement to restore CHO and energy balance (Ex-Bal). The exercise session in Ex-Def and Ex-Bal consisted of 90 min cycle ergometry at 70% peak oxygen uptake (Vo(2peak)) followed by 10 maximal 1-min sprints. CHO replacement was achieved using glucose solutions consumed at 0, 2, and 4 h postexercise. Muscle glycogen was 40 +/- 4% (P < 0.05) and 94 +/- 3% (P = 0.24) of Con values on the morning of the Ex-Def and Ex-Bal OFTT, respectively. Postprandial TG were 40 +/- 14% lower and postprandial HDL-C, free fatty acids, and 3-hydroxybutyrate were higher in Ex-Def compared with Con (P < 0.05). Most importantly, these exercise effects were not evident in Ex-Bal. Postprandial insulin and glucose and the homeostatic model assessment of insulin resistance (HOMA(IR)) were not significantly different across trials. There was no relation between the changes in postprandial TG and muscle glycogen across trials. In conclusion, the influence of acute exhaustive exercise on postprandial lipid metabolism is largely dependent on the associated CHO and energy deficit.

  3. Global Crustal Dynamics of Magnetars in Relation to Their Bright X-Ray Outbursts

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Thompson, Christopher; Yang, Huan; Ortiz, Néstor

    2017-05-20

    This paper considers the yielding response of a neutron star crust to smooth, unbalanced Maxwell stresses imposed at the core–crust boundary, and the coupling of the dynamic crust to the external magnetic field. Stress buildup and yielding in a magnetar crust are global phenomena: an elastic distortion radiating from one plastically deforming zone is shown to dramatically increase the creep rate in distant zones. Runaway creep to dynamical rates is shown to be possible, being enhanced by in situ heating and suppressed by thermal conduction and shearing of an embedded magnetic field. A global and time-dependent model of elastic, plastic,more » magnetic, and thermal evolution is developed. Fault-like structures develop naturally, and a range of outburst timescales is observed. Transient events with time profiles similar to giant magnetar flares (millisecond rise, ∼0.1 s duration, and decaying power-law tails) result from runaway creep that starts in localized sub-kilometer-sized patches and spreads across the crust. A one-dimensional model of stress relaxation in the vertically stratified crust shows that a modest increase in applied stress allows embedded magnetic shear to escape the star over ∼3–10 ms, dissipating greater energy if the exterior field is already sheared. Several such zones coupled to each other naturally yield a burst of duration ∼0.1 s, as is observed over a wide range of burst energies. The collective interaction of many plastic zones forces an overstability of global elastic modes of the crust, consistent with quasi-periodic oscillation (QPO) activity extending over ∼100 s. Giant flares probably involve sudden meltdown in localized zones, with high-frequency (≫100 Hz) QPOs corresponding to standing Alfvén waves within these zones.« less

  4. Synthesis and Characterization of Self-Standing and Highly Flexible δ-MnO2@CNTs/CNTs Composite Films for Direct Use of Supercapacitor Electrodes.

    PubMed

    Wu, Peng; Cheng, Shuang; Yang, Lufeng; Lin, Zhiqiang; Gui, Xuchun; Ou, Xing; Zhou, Jun; Yao, Minghai; Wang, Mengkun; Zhu, Yuanyuan; Liu, Meilin

    2016-09-14

    Self-standing and flexible films worked as pseudocapacitor electrodes have been fabricated via a simple vacuum-filtration procedure to stack δ-MnO2@carbon nanotubes (CNTs) composite layer and pure CNT layer one by one with CNT layers ended. The lightweight CNTs layers served as both current collector and supporter, while the MnO2@CNTs composite layers with birnessite-type MnO2 worked as active layer and made the main contribution to the capacitance. At a low discharge current of 0.2 A g(-1), the layered films displayed a high areal capacitance of 0.293 F cm(-2) with a mass of 1.97 mg cm(-2) (specific capacitance of 149 F g(-1)) and thickness of only 16.5 μm, and hence an volumetric capacitance of about 177.5 F cm(-3). Moreover, the films also exhibited a good rate capability (only about 15% fading for the capacitance when the discharge current increased to 5 A g(-1) from 0.2 A g(-1)), outstanding cycling stability (about 90% of the initial capacitance was remained after 5,000 cycles) and high flexibility (almost no performance change when bended to different angles). In addition, the capacitance of the films increased proportionally with the stacked layers and the geometry area. E.g., when the stacked layers were three times many with a mass of 6.18 mg cm(-2), the areal capacitance of the films was increased to 0.764 F cm(-2) at 0.5 A g(-1), indicating a high electronic conductivity. It is not overstated to say that the flexible and lightweight layered films emerged high potential for future practical applications as supercapacitor electrodes.

  5. Does work-to-family conflict really matter for health? Cross-sectional, prospective cohort and fixed-effects analyses.

    PubMed

    Oshio, Takashi; Inoue, Akiomi; Tsutsumi, Akizumi

    2017-02-01

    It is well known that work-to-family conflict (WFC) is negatively associated with employees' health outcomes, including mental health and health behavior. However, the associations may be overstated because of insufficient control for unobserved individual attributes. To address this possibility, we compared the associations between WFC and health observed from a cross-sectional, prospective cohort and from fixed-effects regression models. We analyzed data from a Japanese occupational cohort survey of 15,102 observations from 7551 individuals (5947 men and 1604 women), which were collected in two waves with a one-year interval. We constructed a binary variable of high WFC and considered psychological distress measured using the Kessler 6 (K6) score, job and life dissatisfaction, and five types of health behavior (current smoking, problem drinking, leisure-time physical inactivity, sickness absence, and refraining from medical care). Results showed that for men, a high WFC increased the probability of reporting psychological distress (K6 score ≥ 5); this increased by 12.4% in a fixed-effects model. The association was substantially limited, as compared to the increase of 30.9% and 23.2% observed in cross-sectional and prospective cohort models, respectively; however, the association remained significant. Similar patterns were observed for job and life dissatisfaction. In contrast, the associations of WFC with all five types of health behavior were non-significant after controlling for fixed effects. We obtained generally similar results for women and found no substantial gender difference in the fixed-effects models. We concluded that the associations of WFC with employees' mental health and subjective well-being were robust, whereas the association between WFC and health behavior was generally limited. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Coordination and Convening of the 2016 Arctic Science Summit Week

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hinzman, Larry D.

    The Arctic Science Summit Week, Arctic Observing Summit, Arctic Council Senior Arctic Officials, Model Arctic Council, and International Arctic Assembly were convened on the campus of the University of Alaska Fairbanks with great productivity and satisfaction of the participants. We were pleased to welcome over 1000 participants from 30 different nations and over 130 different institutions. The organization and execution of these meetings was extensive and complex involving more than 250 coordinators, volunteers and contributors from across Alaska. The participants were enthusiastic in their praise of the content and accomplishments of the meeting, but they were equally happy about themore » genuine welcome offered to our guests by the people of Alaska. Hosting a complex event such as this summit required an army of supporting services and we were blessed to have volunteers from Fairbanks, North Pole, Anchorage and other communities throughout Alaska helping us meet these needs. This truly was an event hosted by the people of Alaska. The significance of these events cannot be overstated. The US and global communities are finally coming to the realization of the important role that the Arctic plays in international politics, economics, and science. The Arctic has experienced tremendous changes in recent years, offering new opportunities that may be addressed through international collaborations, and serious challenges that must be addressed through active investment, adaptation and national and international coordination. Over 10% of the meeting participants were indigenous peoples, from indigenous organizations or hailed from small remote communities. This is still lower than we had hoped, but it is greater participation than similar meetings have experienced in the past. It is through such engagement that we can attack problems related to the changing environment, stagnant economies, and social ills.« less

  7. Characteristics and analysis of scientific articles submitted to the European Annals of Otorhinolaryngology, Head and Neck Diseases.

    PubMed

    Laccourreye, O; Bonfils, P; Denoyelle, F; Garrel, R; Jankowski, R; Karkas, A; Makeieff, M; Righini, C; Vincent, C; Martin, C

    2015-09-01

    To evaluate characteristics, suggested modifications and reasons for rejection in scientific articles submitted for publication in the European Annals of Otorhinolaryngology, Head and Neck Diseases. A prospective study analyzed the flaws noted by reviewers in 52 scientific articles submitted to the European Annals of Otorhinolaryngology, Head and Neck Diseases between August 31, 2014 and February 28, 2015. Fifteen flaws concerning content and 7 concerning form were identified. In more than 25% of submissions, major flaws were noted: purely descriptive paper; lack of contribution to existing state of knowledge; failure to define a clear study objective and/or analyze the impact of major variables; poorly structured Materials and methods section, lacking description of study population, objective and/or variables; lack of or inappropriate statistical analysis; Introduction verbose and/or misrepresenting the literature; excessively heterogeneous and/or poorly described study population; imprecise discussion, straying from the point, overstating the significance of results and/or introducing new results not mentioned in the Results section; description of the study population placed in the Results section instead of under Materials and methods; serious mistakes of syntax, spelling and/or tense; and failure to follow the Instructions to Authors. After review, 21.1% of articles were published, 65.3% rejected and 13.4% non-resubmitted within 3 months of review. On univariate analysis, the only variable increasing the percentage of articles accepted was the topic not being devoted to head and neck surgery (P=0.03). These results document the excessive flaw rate still to be found in manuscripts and demonstrate the continuing need for authors to master and implement the rules of scientific medical writing. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  8. Dissemination of 2014 dual antiplatelet therapy (DAPT) trial results: a systematic review of scholarly and media attention over 7 months

    PubMed Central

    Haneef, Romana; Ravaud, Philippe

    2017-01-01

    Objective To explore how the results from the 2014 dual antiplatelet therapy (DAPT) trial were disseminated to the scientific community and online media. Design A a systematic review of scholarly and public attention surrounding the DAPT study. Settings Data were collected from the ISI Web of Knowledge, Google Scholar, PubMed Commons, EurekAlert, the DAPT study website (www.daptstudy.org) and the New England Journal of Medicine website (for scholarly attention) and Altmetric Explorer, Snap Bird, YouTube (for public attention) citing DAPT study results appearing from 16 November 2014 to 10 June 2015. Participants No participants were involved in this study. Main outcome measure Proportion of contents highlighting the increased risk of mortality and critical to the author’s interpretation of the results. Results We identified 425 items reported by seven sources; 164 (39%) disseminated the authors’ interpretation via an electronic link or a reference, with no additional text. Among 81 items (19 %), the message favoured prolonged treatment and consequently overstated the article conclusions. Among 119 items (28 %), the text was uncertain about the benefit of prolonged treatment but was reported with no or inappropriate mention of increased risk of mortality. Only 34 items (8 %) were uncertain about the benefit of prolonged treatment and mentioned increased risk of mortality. In all, 27 items (6 %) did not favour prolonged treatment, and only 12 of these (3 %) clearly raised some concerns about the reporting of increased risk of death. Conclusion Dissemination of the DAPT study results to the scientific community and on different media sources rarely criticised the interpretation of the study results. PMID:29101129

  9. How Well Does Medicaid Work in Improving Access to Care?

    PubMed Central

    Long, Sharon K; Coughlin, Teresa; King, Jennifer

    2005-01-01

    Objective To provide an assessment of how well the Medicaid program is working at improving access to and use of health care for low-income mothers. Data Source/Study Setting The 1997 and 1999 National Survey of America's Families, with state and county information drawn from the Area Resource File and other sources. Study Design Estimate the effects of Medicaid on access and use relative to private coverage and being uninsured, using instrumental variables methods to control for selection into insurance status. Data Collection/Extraction Method This study combines data from 1997 and 1999 for mothers in families with incomes below 200 percent of the federal poverty level. Principal Findings We find that Medicaid beneficiaries' access and use are significantly better than those obtained by the uninsured. Analysis that controls for insurance selection shows that the benefits of having Medicaid coverage versus being uninsured are substantially larger than what is estimated when selection is not accounted for. Our results also indicate that Medicaid beneficiaries' access and use are comparable to that of the low-income privately insured. Once insurance selection is controlled for, access and use under Medicaid is not significantly different from access and use under private insurance. Without controls for insurance selection, access and use for Medicaid beneficiaries is found to be significantly worse than for the low-income privately insured. Conclusions Our results show that the Medicaid program improved access to care relative to uninsurance for low-income mothers, achieving access and use levels comparable to those of the privately insured. Our results also indicate that prior research, which generally has not controlled for selection into insurance coverage, has likely understated the gains of Medicaid relative to uninsurance and overstated the gains of private coverage relative to Medicaid. PMID:15663701

  10. The archaeology, chronology and stratigraphy of Madjedbebe (Malakunanja II): A site in northern Australia with early occupation.

    PubMed

    Clarkson, Chris; Smith, Mike; Marwick, Ben; Fullagar, Richard; Wallis, Lynley A; Faulkner, Patrick; Manne, Tiina; Hayes, Elspeth; Roberts, Richard G; Jacobs, Zenobia; Carah, Xavier; Lowe, Kelsey M; Matthews, Jacqueline; Florin, S Anna

    2015-06-01

    Published ages of >50 ka for occupation at Madjedbebe (Malakunanja II) in Australia's north have kept the site prominent in discussions about the colonisation of Sahul. The site also contains one of the largest stone artefact assemblages in Sahul for this early period. However, the stone artefacts and other important archaeological components of the site have never been described in detail, leading to persistent doubts about its stratigraphic integrity. We report on our analysis of the stone artefacts and faunal and other materials recovered during the 1989 excavations, as well as the stratigraphy and depositional history recorded by the original excavators. We demonstrate that the technology and raw materials of the early assemblage are distinctive from those in the overlying layers. Silcrete and quartzite artefacts are common in the early assemblage, which also includes edge-ground axe fragments and ground haematite. The lower flaked stone assemblage is distinctive, comprising a mix of long convergent flakes, some radial flakes with faceted platforms, and many small thin silcrete flakes that we interpret as thinning flakes. Residue and use-wear analysis indicate occasional grinding of haematite and woodworking, as well as frequent abrading of platform edges on thinning flakes. We conclude that previous claims of extensive displacement of artefacts and post-depositional disturbance may have been overstated. The stone artefacts and stratigraphic details support previous claims for human occupation 50-60 ka and show that human occupation during this time differed from later periods. We discuss the implications of these new data for understanding the first human colonisation of Sahul. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Heroin users' views and experiences of physical activity, sport and exercise.

    PubMed

    Neale, Joanne; Nettleton, Sarah; Pickering, Lucy

    2012-03-01

    Although there is limited research on heroin users' participation in physical activity, sport and exercise, public health literature asserts that being physically active is good for individuals. Critics, however, caution that the benefits of sport and exercise are overstated and sport may itself reinforce or create inequalities. In-depth interviews were conducted with 40 current or ex-heroin users, of whom 37 were re-interviewed three months later. Data from all 77 interviews were analysed to explore individuals' self-reported participation in physical activity, sport and exercise; their desire to participate; and any barriers to participation experienced. Participants were very interested in sport and exercise and engaged in a wide variety of active pastimes. Although they did little structured sport or exercise during periods of heavy heroin use, they still often walked or cycled. Enjoyment was a key feature of being physically active in treatment and in early recovery. Additionally, individuals reported diverse health and social gains and felt that sport and exercise helped them to reduce their heroin use. These benefits notwithstanding, there were personal, social and structural barriers to being active and so individuals were generally keen to take advantage of any sport or exercise opportunities offered to them by services. By focusing on the meanings that heroin users themselves attribute to being active, our analyses reveal that members of this population derive great pleasure from all manner of physical pastimes. A small but growing literature on embodied sporting practices helps us to interpret this. We conclude that there is an important role for physical activity, sport and exercise within policy and practice responses to heroin use, but with a need to be creative and flexible regarding the kinds of activities promoted. Copyright © 2011 Elsevier B.V. All rights reserved.

  12. Non-invasive Prenatal Testing and the Unveiling of an Impaired Translation Process.

    PubMed

    Murdoch, Blake; Ravitsky, Vardit; Ogbogu, Ubaka; Ali-Khan, Sarah; Bertier, Gabrielle; Birko, Stanislav; Bubela, Tania; De Beer, Jeremy; Dupras, Charles; Ellis, Meika; Granados Moreno, Palmira; Joly, Yann; Kamenova, Kalina; Master, Zubin; Marcon, Alessandro; Paulden, Mike; Rousseau, François; Caulfield, Timothy

    2017-01-01

    Non-invasive prenatal testing (NIPT) is an exciting technology with the potential to provide a variety of clinical benefits, including a reduction in miscarriages, via a decline in invasive testing. However, there is also concern that the economic and near-future clinical benefits of NIPT have been overstated and the potential limitations and harms underplayed. NIPT, therefore, presents an opportunity to explore the ways in which a range of social pressures and policies can influence the translation, implementation, and use of a health care innovation. NIPT is often framed as a potential first tier screen that should be offered to all pregnant women, despite concerns over cost-effectiveness. Multiple forces have contributed to a problematic translational environment in Canada, creating pressure towards first tier implementation. Governments have contributed to commercialization pressure by framing the publicly funded research sector as a potential engine of economic growth. Members of industry have an incentive to frame clinical value as beneficial to the broadest possible cohort in order to maximize market size. Many studies of NIPT were directly funded and performed by private industry in laboratories lacking strong independent oversight. Physicians' fear of potential liability for failing to recommend NIPT may further drive widespread uptake. Broad social endorsement, when combined with these translation pressures, could result in the "routinization" of NIPT, thereby adversely affecting women's reproductive autonomy. Policymakers should demand robust independent evidence of clinical and public health utility relevant to their respective jurisdictions before making decisions regarding public funding for NIPT. Copyright © 2017 The Society of Obstetricians and Gynaecologists of Canada/La Société des obstétriciens et gynécologues du Canada. Published by Elsevier Inc. All rights reserved.

  13. Standards and Methodological Rigor in Pulmonary Arterial Hypertension Preclinical and Translational Research.

    PubMed

    Provencher, Steeve; Archer, Stephen L; Ramirez, F Daniel; Hibbert, Benjamin; Paulin, Roxane; Boucherat, Olivier; Lacasse, Yves; Bonnet, Sébastien

    2018-03-30

    Despite advances in our understanding of the pathophysiology and the management of pulmonary arterial hypertension (PAH), significant therapeutic gaps remain for this devastating disease. Yet, few innovative therapies beyond the traditional pathways of endothelial dysfunction have reached clinical trial phases in PAH. Although there are inherent limitations of the currently available models of PAH, the leaky pipeline of innovative therapies relates, in part, to flawed preclinical research methodology, including lack of rigour in trial design, incomplete invasive hemodynamic assessment, and lack of careful translational studies that replicate randomized controlled trials in humans with attention to adverse effects and benefits. Rigorous methodology should include the use of prespecified eligibility criteria, sample sizes that permit valid statistical analysis, randomization, blinded assessment of standardized outcomes, and transparent reporting of results. Better design and implementation of preclinical studies can minimize inherent flaws in the models of PAH, reduce the risk of bias, and enhance external validity and our ability to distinguish truly promising therapies form many false-positive or overstated leads. Ideally, preclinical studies should use advanced imaging, study several preclinical pulmonary hypertension models, or correlate rodent and human findings and consider the fate of the right ventricle, which is the major determinant of prognosis in human PAH. Although these principles are widely endorsed, empirical evidence suggests that such rigor is often lacking in pulmonary hypertension preclinical research. The present article discusses the pitfalls in the design of preclinical pulmonary hypertension trials and discusses opportunities to create preclinical trials with improved predictive value in guiding early-phase drug development in patients with PAH, which will need support not only from researchers, peer reviewers, and editors but also from academic institutions, funding agencies, and animal ethics authorities. © 2018 American Heart Association, Inc.

  14. Predictors of Long-Term Results After Treatment of Iliac Artery Obliteration by Transluminal Angioplasty and Stent Deployment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Funovics, M.A.; Lackner, B.; Cejna, M.

    2002-10-15

    Purpose: To investigate initial and long-term success rate after percutaneous treatment of iliac artery occlusion with angioplasty and stent deployment. To investigate the influence of vascular comorbidity, lesion length, stent placement and lesion coverage as possible predictors of outcome. Methods: Between January 1994 and December 1999, 80 iliac recanalizations were performed on 78 patients, median age 61.1 {+-}11.5 (SD) years. All patients were followed up by clinical examinations, duplex ultrasound and intravenous digital subtraction angiography. Mean follow-up time was 2.0 {+-} 1.53 (SD) years.Multivariate Cox regression analysis was used to determine the influence of cofactors on patency. Results: One, 2more » and 4 years after recanalization, primary patency was 78.1%, 74.5% and 64.0%; secondary patency was 88.8%, 88.8% and 77.9%, respectively.Patients with shorter occlusions, complete lesion coverage and patent ipsilateral femoral arteries had significantly longer patency rates.Complications included inguinal hematoma (n=1), technical failure (n=3) aortic dissection (n=1), embolic occlusions (n=7), gluteal claudication (n=1) and genital necrosis after subsequent urethral surgery in one patient with contralateral occlusion and ipsilateral overstenting of the internal iliac artery with subsequent stenosis. Complications were of permanent clinical significance in seven of 78 (9%) of the patients. In 17 (22%) cases, percutaneous reintervention was performed with angioplasty in the stent (n=16) or deployment of a new stent (n=1). Conclusion: Endoluminal stent placement has its place in an interdisciplinary therapeutic approach as a viable therapeutic alternative to major transabdominal bypass surgery and can be performed with comparable complication rates. Patients with short occlusions, patent femoral arteries, and stents covering the entire occlusion have significant longer patency.« less

  15. Evidence-based economic analysis demonstrates that ecosystem service benefits of water hyacinth management greatly exceed research and control costs

    PubMed Central

    Harms, Nathan E.; Magen, Cedric; Liang, Dong; Nesslage, Genevieve M.; McMurray, Anna M.; Cofrancesco, Al F.

    2018-01-01

    Invasive species management can be a victim of its own success when decades of effective control cause memories of past harm to fade and raise questions of whether programs should continue. Economic analysis can be used to assess the efficiency of investing in invasive species control by comparing ecosystem service benefits to program costs, but only if appropriate data exist. We used a case study of water hyacinth (Eichhornia crassipes (Mart.) Solms), a nuisance floating aquatic plant, in Louisiana to demonstrate how comprehensive record-keeping supports economic analysis. Using long-term data sets, we developed empirical and spatio-temporal simulation models of intermediate complexity to project invasive species growth for control and no-control scenarios. For Louisiana, we estimated that peak plant cover would be 76% higher without the substantial growth rate suppression (84% reduction) that appeared due primarily to biological control agents. Our economic analysis revealed that combined biological and herbicide control programs, monitored over an unusually long time period (1975–2013), generated a benefit-cost ratio of about 34:1 derived from the relatively modest costs of $124 million ($2013) compared to the $4.2 billion ($2013) in benefits to anglers, waterfowl hunters, boating-dependent businesses, and water treatment facilities over the 38-year analysis period. This work adds to the literature by: (1) providing evidence of the effectiveness of water hyacinth biological control; (2) demonstrating use of parsimonious spatio-temporal models to estimate benefits of invasive species control; and (3) incorporating activity substitution into economic benefit transfer to avoid overstating benefits. Our study suggests that robust and cost-effective economic analysis is enabled by good record keeping and generalizable models that can demonstrate management effectiveness and promote social efficiency of invasive species control. PMID:29844976

  16. Evidence-based economic analysis demonstrates that ecosystem service benefits of water hyacinth management greatly exceed research and control costs.

    PubMed

    Wainger, Lisa A; Harms, Nathan E; Magen, Cedric; Liang, Dong; Nesslage, Genevieve M; McMurray, Anna M; Cofrancesco, Al F

    2018-01-01

    Invasive species management can be a victim of its own success when decades of effective control cause memories of past harm to fade and raise questions of whether programs should continue. Economic analysis can be used to assess the efficiency of investing in invasive species control by comparing ecosystem service benefits to program costs, but only if appropriate data exist. We used a case study of water hyacinth ( Eichhornia crassipes (Mart.) Solms), a nuisance floating aquatic plant, in Louisiana to demonstrate how comprehensive record-keeping supports economic analysis. Using long-term data sets, we developed empirical and spatio-temporal simulation models of intermediate complexity to project invasive species growth for control and no-control scenarios. For Louisiana, we estimated that peak plant cover would be 76% higher without the substantial growth rate suppression (84% reduction) that appeared due primarily to biological control agents. Our economic analysis revealed that combined biological and herbicide control programs, monitored over an unusually long time period (1975-2013), generated a benefit-cost ratio of about 34:1 derived from the relatively modest costs of $124 million ($2013) compared to the $4.2 billion ($2013) in benefits to anglers, waterfowl hunters, boating-dependent businesses, and water treatment facilities over the 38-year analysis period. This work adds to the literature by: (1) providing evidence of the effectiveness of water hyacinth biological control; (2) demonstrating use of parsimonious spatio-temporal models to estimate benefits of invasive species control; and (3) incorporating activity substitution into economic benefit transfer to avoid overstating benefits. Our study suggests that robust and cost-effective economic analysis is enabled by good record keeping and generalizable models that can demonstrate management effectiveness and promote social efficiency of invasive species control.

  17. You might as well smoke; the misleading and harmful public message about smokeless tobacco.

    PubMed

    Phillips, Carl V; Wang, Constance; Guenzel, Brian

    2005-04-05

    Compared to smoking cigarettes, use of Western smokeless tobacco (ST) products is associated with a very small risk of life-threatening disease (with estimates in the range of a few percent of the risk from smoking, or even less). This means that smokers can realize substantial health benefits by switching to ST, an obvious substitute. But consumers and policy makers have little chance of learning that ST is much less dangerous than smoking because popular information provided by experts and advocates overstates the health risks from ST relative to cigarettes. To examine the extent of this overstatement in one medium, we conducted a systematic review of websites containing information about ST and health risks. We examined the content of 316 relevant websites identified by a Google search. We found that when any substantive information about the risk from ST is given, the risk is almost universally conflated with the risk from cigarettes. Accurate comparative risk information was quite rare, provided by only a handful of websites, all appearing low in our search results (i.e., of low popularity and thus unlikely to be found by someone searching for information). About 1/3 of the websites, including various authoritative entities, explicitly claimed that ST is as bad as or worse than cigarettes. Most of the other sites made statements that imply the risks are comparable. Through these websites, and presumably other information provided by the same government, advocacy, and educational organizations, ST users are told, in effect, that they might as well switch to smoking if they like it a bit more. Smokers and policy makers are told there is no potential for harm reduction. These messages are clearly false and likely harmful, representing violations of ethical standards.

  18. An Ecological Assessment of the Pandemic Threat of Zika Virus

    PubMed Central

    Getz, Wayne

    2016-01-01

    The current outbreak of Zika virus poses a severe threat to human health. While the range of the virus has been cataloged growing slowly over the last 50 years, the recent explosive expansion in the Americas indicates that the full potential distribution of Zika remains uncertain. Moreover, many studies rely on its similarity to dengue fever, a phylogenetically closely related disease of unknown ecological comparability. Here we compile a comprehensive spatially-explicit occurrence dataset from Zika viral surveillance and serological surveys based in its native range, and construct ecological niche models to test basic hypotheses about its spread and potential establishment. The hypothesis that the outbreak of cases in Mexico and North America are anomalous and outside the native ecological niche of the disease, and may be linked to either genetic shifts between strains, or El Nino or similar climatic events, remains plausible at this time. Comparison of the Zika niche against the known distribution of dengue fever suggests that Zika is more constrained by the seasonality of precipitation and diurnal temperature fluctuations, likely confining autochthonous non-sexual transmission to the tropics without significant evolutionary change. Projecting the range of the diseases in conjunction with three major vector species (Aedes africanus, Ae. aegypti, and Ae. albopictus) that transmit the pathogens, under climate change, suggests that Zika has potential for northward expansion; but, based on current knowledge, our models indicate Zika is unlikely to fill the full range its vectors occupy, and public fear of a vector-borne Zika epidemic in the mainland United States is potentially informed by biased or limited scientific knowledge. With recent sexual transmission of the virus globally, we caution that our results only apply to the vector-borne transmission route of the pathogen, and while the threat of a mosquito-carried Zika pandemic may be overstated in the media, other transmission modes of the virus may emerge and facilitate naturalization worldwide. PMID:27564232

  19. An interdisciplinary, outcome-based approach to astmospheric CO2 mitigation with planted southern pine forests

    NASA Astrophysics Data System (ADS)

    Martin, T.; Fox, T.; Peter, G.; Monroe, M.

    2012-12-01

    The Pine Integrated Network: Education, Mitigation and Adaptation Project ("PINEMAP") was funded by National Institute of Food and Agriculture to produce outcomes of enhanced climate change mitigation and adaptation in planted southern pine ecosystems. The PINEMAP project leverages a strong group of existing networks to produce synergy and cooperation on applied forestry research in the region. Over the last 50 years, cooperative research on planted southern pine management among southeastern U.S. universities, government agencies, and corporate forest landowners has developed and facilitated the widespread implementation of improved genetic and silvicultural technology. The impact of these regional research cooperatives is difficult to overstate, with current members managing 55% of the privately owned planted pine forestland, and producing 95% of the pine seedlings planted each year. The PINEMAP team includes the eight major forestry cooperative research programs, scientists from eleven land grant institutions, the US Forest Service, and climate modeling and adaptation specialists associated with the multi-state SE Climate Consortium and state climate offices. Our goal is to create and disseminate the knowledge that enables landowners to: harness planted pine forest productivity to mitigate atmospheric CO2; more efficiently use nitrogen and other fertilizer inputs; and adapt their forest management to increase resilience in the face of changing climate. We integrate our team's infrastructure and expertise to: 1) develop breeding, genetic deployment and innovative management systems to increase C sequestration and resilience to changing climate of planted southern pine forests ; 2) understand interactive effects of policy, biology, and climate change on sustainable management; 3) transfer new management and genetic technologies to private industrial and non-industrial landowners; and 4) educate a diverse cross-section of the public about the relevance of forests, forest management, and climate change. These efforts will enable our stakeholders to enhance the productivity of southern pine forests, while maintaining social, economic, and ecological sustainability.

  20. Sea Level, Land Motion, and the Anomalous Tide at Churchill, Hudson Bay

    NASA Astrophysics Data System (ADS)

    Ray, R. D.

    2015-12-01

    The importance of the tide gauge at Churchill, Manitoba, cannot be overstated. It is the only permanently operating tide gauge in the central Canadian Arctic, and it sits on a prime spot for monitoring the mantle's rebound from the Laurentide ice loss. Yet interpretation of the sea-level time series at Churchill has long been problematic, going back even to early work by Gutenberg in the 1940s. The long-term relative sea-level rates are inconsistent: approximately -4, -19, -5 ± 1 mm/y for the periods 1940-1970, 1970-1990, 1990-2014 respectively. Annual mean high water (MHW) and mean low water (MLW) reflect these trends until around 1990, after which MLW leveled off and is now nearly unchanging. Slightly later, around 2000, the semidiurnal tides became very anomalous, with falling amplitudes and slightly increasing phase lags. The amplitude of M2 was approximately 154 cm before 2000; it dropped to about 146 cm by 2010 and reached an all-time low of 142 cm in 2014. Satellite altimeter estimates of the tide in this region, although challenging because of seasonal ice cover, show no comparable M2 changes, so the tidal changes must be localized to the near vicinity of the gauge (or to the gauge itself if caused by a malfunction). On the other hand, altimetry confirms the post-1992 Churchill measurements of mean sea level, thanks to the long time series of land motion measurements obtained at GPS station CHUR, which gives a vertical uplift of 10.1 mm/y. Combining satellite altimeter data with the Churchill tide-gauge data gives an implied vertical crustal rate of about 9.0 ± 0.8 mm/y, in reasonable agreement with the GPS. In summary, we have still anomalous MSL measurements at the Churchill gauge for the intermediate 1970-1990 era, and very anomalous tidal measurements since 2000, but we have apparently quite reliable MSL rates since 1990.

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